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APPN ASIA PACIFIC NEWSLETTER

September 2012 • Volume 1 • Number 2 A publication of the SEATPA and IAS@NTU

A Centenary Celebration of the Life and of Madame Chien-Shiung Wu Scientific Achievements of Prof. Chien Shiung Wu My Life as a Boson: The Story of “The Higgs” Satyedra Nath Bose – His Life and

World Scientific Connecting Great Minds

FORTHCOMING TITLE BASED ON FIRST WOLF PRIZE WINNER MADAME CHIEN-SHIUNG WU The First Lady of Physics Research

by Tsai-Chien Chiang & translated by Tang-Fong Wong

Chinese biographies of scientists were usually written in a naïve and superficial way, therefore not worth reading. This book, however, seriously and honestly presents the humanity and background of the success of Wu Chien-Shiung. It opens a new era of such biographies. Chen Ning Yang, Nobel laureate

This book presents an unbiased account of Wu’s life as well as lasting achievements in physics. Her deep views and observations, creativity and determination made her a most successful scientist and a distinguished human being. The author has done serious research, and has written accurately and eloquently. It is an accurate, in-depth masterpiece of study about the life and unusual achievements of one of the world’s greatest physicist.

Samuel C. C. Ting, Nobel laureate

The life of Professor Wu is indeed an enviable, rich history of a distinguished scientist, full of admirable achievements and struggles. Her scientific career had many exciting incidents worth studying by young scientists. I am very arrating the well-lived life of the “Chinese Madame Curie” — a recipient of the first Wolf Prize in Physics (1978), the first woman happy to see this masterpiece of Chiang Tsai-Chien. He did to receive an honorary doctorate from Princeton University, as well his research diligently on the life of Wu, and wrote the book N as the first female president of the American Physics Society — this book with discipline and professionalism. I believe that this provides a comprehensive and honest account of the life of Dr Chien-Shiung biography will inspire many young scholars to advance Wu, an outstanding and leading experimental physicist of the 20th century. forward, and make many young people understand that : Students and laymen. there are not many more meaningful careers than scientific Readership research. 300pp Dec 2012 Lee Yuan-Tseh, Nobel laureate 978-981-4374-84-2 US$98 £65 978-981-4368-92-6(pbk) US$48 £32

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AD-JK-07-12-05-W.indd 1 9/24/12 11:12 AM Connecting Great Minds

FORTHCOMING TITLE BASED ON FIRST WOLF PRIZE WINNER APPN ASIA PACIFIC PHYSICS NEWSLETTER MADAME CHIEN-SHIUNG WU September 2012 • Volume 1 • Number 2 A publication of the SEATPA and IAS@NTU Singapore Asia Pacific Physics Newsletter publishes articles reporting frontier discoveries in EDITORIAL The First Lady of Physics Research physics, research highlights, and news to facilitate interaction, collaboration and 3 by Tsai-Chien Chiang & translated by Tang-Fong Wong cooperation among physicists in Asia Pacific physics community. COMMENT The Elementary Physics Research in Singapore: the Editor-in-Chief 4 Kok Khoo Phua Past, the Present and the Future Kok Khoo Phua Chinese biographies of scientists were usually written in a SEATPA Committee naïve and superficial way, therefore not worth reading. This Christopher C Bernido book, however, seriously and honestly presents the humanity Phil Chan Leong Chuan Kwek News and background of the success of Wu Chien-Shiung. It opens Choy Heng Lai 5 Hiroaki Aihara Elected Chair of IUPAP Commission C11 of a new era of such biographies. Swee Cheng Lim Ren Bao Liu and Fields Chen Ning Yang, Nobel laureate Hwee Boon Low Fifth ASTROD Symposium and Outlook of Direct Anh Ký Nguyên This book presents an unbiased account of Wu’s life as well Choo Hiap Oh Gravitational- Detection K. G. Arun, Bala R. Iyer, Wei-Tou Ni as lasting achievements in physics. Her deep views and Kok Khoo Phua Roh Suan Tung observations, creativity and determination made her a most Preecha Yupapin Third International Symposium on Nanoscience successful scientist and a distinguished human being. The Hishamuddin Zainuddin Shuyan Xu author has done serious research, and has written Freddy Zen accurately and eloquently. It is an accurate, in-depth Managing Editor masterpiece of study about the life and unusual Roh Suan Tung RESEARCH HIGHLIGHTS achievements of one of the world’s greatest physicist. 13 -Orbit Coupled Quantum Gases Senior Publishing Editor Hui Zhai Samuel C. C. Ting, Nobel laureate Fang Zhang Highlights from the Asia Pacific Region The life of Professor Wu is indeed an enviable, rich history Publishing Editors Yu Song of a distinguished scientist, full of admirable achievements Kai Wang and struggles. Her scientific career had many exciting (a) (b) incidents worth studying by young scientists. I am very arrating the well-lived life of the “Chinese Madame Curie” — a Graphic Designer recipient of the first Wolf Prize in Physics (1978), the first woman happy to see this masterpiece of Chiang Tsai-Chien. He did Chuan Ming Loo to receive an honorary doctorate from Princeton University, as well p13 p16 p17 his research diligently on the life of Wu, and wrote the book N as the first female president of the American Physics Society — this book with discipline and professionalism. I believe that this provides a comprehensive and honest account of the life of Dr Chien-Shiung biography will inspire many young scholars to advance Wu, an outstanding and leading experimental physicist of the 20th century. forward, and make many young people understand that Articles : Students and laymen. there are not many more meaningful careers than scientific Readership 32 -Shift in the OPERA Setup research. 300pp Dec 2012 Antonino Zichichi Lee Yuan-Tseh, Nobel laureate 978-981-4374-84-2 US$98 £65 The Daya Bay experiment and the Discovery of a new type of 978-981-4368-92-6(pbk) US$48 £32 Oscillation Yifang Wang Cover: Madame Chien-Shiung Wu (Courtesy of Vincent Yuan)

AD-JK-07-12-05-W Preferred Publisher of Leading Thinkers

AD-JK-07-12-05-W.indd 1 9/24/12 11:12 AM Asia Pacific Physics Newsletter PEOPLE (APPN) 50 My Life as a Boson: The Story of “The Higgs” is published jointly by South East Asia Association (SEATPA) and Institute of Advanced Studies, Nanyang Technological University (IAS@NTU) HISTORY 52 Scientific Achievements of SEATPA and IAS@NTU Prof. Chien Shiung Wu Address: Tan Lu 60 Nanyang View #02-18 Singapore 639673 Tel: +65 6513 7660 Fax: +65 6794 4941 – His Life and Times seatpa.org Kameshwar C. Wali ntu.edu.sg/ias

APPN is distributed by World Scientific Publishing Co. Pte. Ltd. p52 Address: 5 Toh Tuck Link Books Singapore 596224 64 Madame Chien-Shiung Wu: The First Lady of Physics Tel: +65 6466 5775 Introduction to Statistical Mechanics Fax: +65 5467 7667 Statistical Mechanics in a Nutshell worldscientific.com

Electronic edition APPN is also available online at: Research Institutes and Labs worldscinet.com/appn 69 IUCAA: Inter-University Centre for Astronomy and Subscriptions , Pune, India APPN is available 4 issues per year For subscription please contact: [email protected]

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Authors APPN welcomes articles with general interests to the physics community. To Institute for Advanced Study: Hong Kong University of Science recommend or contribute news, articles, and Technology history, book reviews, please write to: [email protected] Conference Calendar 74 Upcoming Conferences in the Asia Pacific Region

The views expressed in this Newsletter belong to the authors, and do not necessarily represent those of the Jobs publishers. 77 Print ISSN: 2251-158X Societies Online ISSN: 2251-1598 80 List of Physical Societies in the Asia Pacific Region MICA (P) 216/07/2012 EDITORIAL

In this issue of Asia Pacific Physics Newsletter (APPN), we especially commemorate the birth centennial of Madame Chien-Shiung Wu.

Madame Wu was born on 31 May 1912 in Taicang, near Shanghai, . She received the first Wolf Prize in Physics for her persistent and successful exploration of the which helped establish the precise form and the non conservation of for the weak interaction. In the history section, Lu Tan reviewed on the Scientific Achievements of Madame Wu.

Based on the discovery of parity violation, the Standard Model for was then established. On 4 July 2012, CERN announced the discovery of the new particle on the LHC with mass between 125-126 GeV, in consistent of the . It is an exciting news especially for the centenary birth of Madame Wu.

We have featured an article by Peter Higgs on My Life as a Boson: The Story of “The Higgs”, and two articles on Neutrino experiments: Time-Shift in the OPERA Setup by Antonino Zichichi and The Daya Bay experiment by Yifang Wang. The name boson was commemorative of the contribution of Indian physicist Satyendra Nath Bose. The article Satyendra Nath Bose – His Life and Times, by Kameshwar C. Wali, describes the story of the historical paper of Bose-Einstein statistics.

We hope that the publication of APPN will facilitate interactions, collaboration and cooperation among physicists in the Asia Pacific physics community. Thanks for all the supports and feedback about APPN. Happy reading!

Editor in Chief

Kok Khoo Phua President, South East Asia Theoretical Physics Association Director, Institute of Advanced Studies, Nanyang Technological University

September 2012, Volume 1 No 2 3 COMMENT The Physics Research in Singapore: the Past, the Present and the Future Kok Khoo Phua

he discovery of the Higgs Boson (or more popularly After the 1980s, Singapore physicists made some known in media as God particle) in early July contribution in elementary particle physics, and the city was hailed as one of the most significant scientific had even become the venue for international conferences Tbreakthrough in the 21st Century, stirring a sensation in and workshops on this subject. For example, we organised the Science community and Media around the world. This the world’s biggest international conference in elementary discovery allows us to reassess our understanding of the particle physics in 1990. The Guest-of-Honour was PM importance of elementary particle physics or high Lee Hsien Loong. As the study of theoretical elementary physics, and how its study has to a certain extent influenced particle physics requires a solid foundation in physics and the direction of future development of scientific research as a mathematics, some physicists in this field thus extended whole. In this article, we want to take a look at how Singapore their research interest into areas like quantum . has fared in this area so far, and discuss some of the issues The Centre of Quantum Technologies (CQT), funded by concerning the policies and directions of the research in the the National Research Foundation (NRF), is a multi-million basic sciences in the Asia Pacific region. dollar research centre, which in a way can be regarded as an Physics research can be classified into two categories, extension of the High Energy Research Group. At present, namely experimental and theoretical physics. The experi- NTU and NUS have some research projects in this area and mental elementary particle physics has focused on mega they have also attracted some world-class visiting scholars research centres since the 1960s. For examples, the European to join them. We have just signed agreement with CERN Organization for Nuclear Research (CERN) in Geneva, for long term collaboration. We are hoping that we could the Fermi Lab in Chicago, and the KEK (High Energy analyse the latest experimental data from CERN and also Accelerator Research Organization) in Tsukuba, Japan, our school teachers and students can visit CERN during the etc. Due to their astronomical budget requirement these summer vacation. It is worth noting that so far, Japan has large-scale scientific infrastructures are either funded by the produced five Nobel Laureates for their theoretical research governments or they are established as collaborative projects in elementary particle physics and they are H. Yukawa, S. amongst several participating countries. Tomonaga, Y. Nambu, M. Kobayashi and T. Maskawa. These Starting from late 1960s, there were a considerable masters were basically homegrown physicists. number of young Singaporean scholars returning from The Singapore Government’s policies on the development Europe and the United States. Most of them were specialised of science and technology have been relatively successful, in theoretical physics, including areas like elementary particle having invested billions in R & D. We can see substantial physics, condensed physics and . results, but I hope the Government can also sponsor They worked diligently and kept a low profile. Since theo- research in theoretical sciences, such as pure and applied retical research required less funding, so despite operating mathematics, theoretical physics, theoretical biology, theo- on a low budget, they had made some meaningful contribu- retical chemistry etc. Small countries like Israel, Switzerland, tions in their respective fields of specialization. One of their Denmark, Sweden, etc. are doing world class research and critical achievements was to link up with the international producing significant results in theoretical science due to the physics community, positioning themselves at the frontier support from the government as well as good environment. of research, keeping abreast with the latest experimental Our science policies should not just provide solutions and results and the progress of theoretical research. Professor results for short term problems of commerce and industry A Salam and Professor C. N. Yang, both Nobel Laureates, but we should look into long term planning like education made multiple visits to Singapore then, and were appointed and culture. as the external examiners of Nanyang University (NU) and the National University of Singapore (NUS). They actively Professor Kok Khoo Phua is the promoted theoretical research in different fields during their Director of Institute of Advanced stay, and brought the research standards to greater heights. Studies, Nanyang Technological NTU and NUS have nurtured numerous Masters and PhD University. The views expressed in graduates since the 1970s, and they have made extensive this article are his personal ones. contributions in academic, private and public service.

4 Asia Pacific Physics Newsletter NEWS Hiroaki Aihara Elected Chair of IUPAP C11 Commission of Particles and Fields

he International Union of Pure Russia, Saudi Arabia, Slovenia, Spain, and , IUPAP, at its Switzerland, , Thailand, Turkey, General Assembly on 4th November Ukraine and USA. There have been remark- T2011, elected Professor Hiroaki Aihara as able results from the Belle Collaboration; the chair of Commission C11 of Particles the research is now leading the world, and and Fields. attracting world-class researchers from all IUPAP was established in 1922. Presently over the world. In 2003, Professor Aihara it has 20 specialized commissions, 4 affili- received the prestigious INOUE Science ated commissions, 12 inter-union groups Foundation Prize, for his significant contri- and 9 working groups for various fields of bution to discovery of CP violation in the physics, among them the Commission 11 on B-meson system in the Belle experiment. Particle and Fields. The mandate of C11 is to Professor Aihara is currently the dean of promote the exchange of information in the field, supervise the School of Science and the deputy director of the Kavli the organization of the major conferences in particle physics, Institute for the Physics and Mathematics of the and maintain the liaison between IUPAP and the Interna- (IPMU) of the University of Tokyo. tional Committee for Future Accelerators (ICFA), which was established by C11 in 1976. One of the most recent major conferences is the 36th International Conference on High Energy Physics (ICHEP2012), which was held in Melbourne IUPAP Commission C11 Members: during 4-11 July 2012. Currently C11 has 14 members and Chair: Hiroaki Aihara (Japan) 1 associated member. Vice Chair: Francois Le Diberder (France) Professor Aihara’s election to this position recognises Secretary: Heidi Schellman (USA) his significant contribution to particle physics, as well as Sergio Ferraz Novaes (Brazil) his contributions to international collaboration of science. Robert Mann (Canada) Professor Hiroaki Aihara received Ph.D. from the Univer- Xiaoyan Shen (China) sity of Tokyo in 1984. At the time, it had been common for Jiří Hořejší (Czech Republic) young Japanese students and researchers in particle physics Thomas Mueller (Germany) to go to the United States to be trained and gain experience, Umbero Dosselli () since particle physics research was originated in the USA. Vladamir Kekelidze (Russia) Professor Aihara had conducted research at Lawrence Kok Khoo Phua (Singapore) Berkeley National Laboratory for about 13 years, including Juan Fuster (Spain) the time when he was a graduate student. Per Olof Hulth (Sweden) Professor Aihara now leads a group in Japan, and the Mark Lancaster (UK), Belle Collaboration to study the origin of CP violation. The collaboration, based on Japan, includes Australia, Austria, Associate member: Soo-Bong Kim (Korea). China, Czech, Germany, India, Korea, Malaysia, Poland,

September 2012, Volume 1 No 2 5 NEWS Fifth ASTROD Symposium and Outlook of Direct Gravitational-Wave Detection

K.G. Arun Chennai Mathematical Institute, Chennai, India

Bala R. Iyer Raman Research Institute, Bangalore, India

Wei-Tou Ni National Tsing Hua University, Hsinchu, Taiwan, ROC

rom July 11 to July 13, 2012, Raman Research Institute (Fig. 1). The aim of this series of Symposia is to focus on (Bangalore, India) hosted the Fifth International various disciplines related to fundamental physics in , to ASTROD Symposium on Laser Astrodynamics, Space foster dialogues and to plan for the future. Previous ASTROD FTest of Relativity and Gravitational-Wave Astronomy. About Symposia were held during September 21-23, 2001 (Beijing), sixty persons attended the Symposium including 24 invited June 2-3, 2005 (Bremen), July 14-16, 2006 (Beijing) and July speakers, 15 professionals from various fields and 20 students 16-17, 2010 (Bremen).

Fig. 1. ASTROD5 group photo

6 Asia Pacific Physics Newsletter NEWS

The inaugural address was made by P. Sreekumar of the In the wake of these developments, a surge of activity in Indian Space Research Organization (ISRO). The focus in precision metrology, instrumentation, data handling and the Symposium was on (GW) detection, computation are expected with LIGO-India as inspiration. especially with space-based interferometers. However, in The laser-interferometric ground detectors are most view of the exciting proposals over the last couple of years sensitive to the high frequency band (10 Hz – 10 kHz). in establishing a global network crucial for GW astronomy, The major sources are coalescences of compact binaries the meeting began with ground based detectors. Daniel Sigg of stars (NSs) and stellar mass Black Holes (BHs), from the LIGO gave the status report on Ground-Based GW and core collapse supernovae. Other promising frequency Interferometers. With the ongoing construction of Advanced bands for direct detection are the middle frequency band (0.1 LIGO (4 km arm length, in Hanford and Livingston, USA), Hz – 10 Hz) and the low frequency band (100 nHz – 0.1 Hz) Advanced Virgo (3 km arm length, in Cascina, Italy) and utilizing space interferometric detectors, and the very low KAGRA (3 km arm length, in Kamioka, Japan), the first GW frequency band (300 pHz – 100 nHz) using Timing detection is anticipated around 2016 and to open an era of Arrays (PTAs). The complete frequency classification of experimental GW Astronomy. GWs is given in http://astrod.wikispaces.com/file/view/ C. S. Unnikrishnan from TIFR summarised the initia- GW-classification.pdf. tives by the IndIGO (Indian Initiative in Gravitational are ultra-stable clocks through precision timing. Wave Observations) Consortium during the past two When very low frequency GWs pass by the line of sight of years which has now materialized into concrete plans and pulsars, they encode periodic signals on the arrival times project opportunities for instrumentation and research of pulses and therefore an array of pulsars emitting pulses based on advanced interferometer detectors. The proposed with ultra-stable periods can serve as a GW detector. The LIGO-India project is a culmination of a 2-year-long intense ground pulse receiver can be a single detector or multiple effort by IndIGO, which will foster integrated development detectors or an array. Dick Manchester (CSIRO) and Bhal of frontier gravitational wave research in India and will Chandra Joshi (NCRA) reviewed pulse timing and reported facilitate direct participation in global GW research with on the sensitivities of current pulsar timing arrays. With substantial contributions to gravitational wave astronomy. the current ranges of prediction of GW backgrounds from

September 2012, Volume 1 No 2 7 NEWS

5 SMBH (supermassive ) — SMBH mergers, these From Fig. 2, we can see that the GWs from 10 MSun mergers 6 background GWs would be detectable by PTAs (Pulsar and 10 MSun mergers have high S/N ratios for NGO/eLISA, Timing Arrays) around 2020. The present upper limits on LISA and ASTROD-GW detectors. the background from PTAs reach 10-15 level of the charac- NGO/eLISA (www.elisa-ngo.org) with its 1 million km teristic strain in the very low frequency band and already arm length is more sensitive in the higher frequency part rule out models in which giant elliptical galaxies grow by of this range. It is 5 times down-scaled from LISA after the merger alone. withdrawal of NASA from the project. Its thorough assess- Direct detection of GWs with high signal to noise ratios ment study was presented by Oliver Jennrich from ESA. Paul would need space missions to realize. Space GW detection McNamara reported the present status of LISA Pathfinder is the main focus of ASTROD5 Symposium. In Bernard (LPF). This technological demonstrator LPF has tested most Schutz's (AEI) talk, GW sources for space detectors were of its systems already and is scheduled for launch in the last reviewed extensively. These sources include: (i) Massive Black quarter of 2014. With the outstanding review of ESA’s Science 3 8 Holes (BHs) (10 –10 MSun): mass function, spin evolution Advisory Board and with the success of LPF, NGO/eLISA is as function of redshift z, sampling central black holes in hoped to be launched around 2025-6. ordinary galaxies, search for intermediate mass BHs (IMBH); ASTROD-GW (ASTROD [Astrodynamical Space Test of (ii) Evolution of the Cosmic Web at high redshift: observa- Relativity using Optical Devices] optimized for GW detec- tion of objects before re-ionisation (BH mergers at z >> 10), tion) is an optimization of ASTROD to focus on the goal testing models of how massive BHs formed and evolved from of detection of GWs. The scientific aim is focused on GW seeds; (iii) Compact WD binaries in the Galaxy: catalogue of detection at low frequency. The mission orbits of the 3 space- white-dwarf (WD) binary systems in the Galaxy, comparison craft (S/C) forming a nearly equilateral triangular array are with GAIA (to be launched in 2013), precise masses and chosen to be near the Sun-Earth Lagrange points L3, L4 and distances for many WD/NS/BH binaries. The fundamental L5 (Fig. 3). The 3 spacecraft range interferometrically with physics with the space based GW detectors include testing one another with arm length about 260 million kilometers. GR in the ultra-strong regime, proving the existence of BH horizons, testing no-hair theorems and cosmic censorship, searching for scalar gravitational fields and other deviations from GR, looking for cosmic GW background, testing the order of the electroweak phase transitions and searching for cosmic strings. The low-frequency space detectors are sensi- tive to the frequency range 100 nHz-100 mHz and have high S/N ratios in detecting these sources. Schutz summarized the sensitivities of these GW detectors in a single slide (Fig. 2).

Fig. 3. Schematic of ASTROD-GW mission orbit configuration.

Since the sensitivities of the space interferometers are limited by local accelerometer noises in the low-frequency limit, the strain (δL/L) sensitivities are inversely proportional to the arm length. In Fig. 2, same local accelerometer noises are assumed. Due to arm length ratio, ASTROD-GW is better in sensitivity in the low-frequency limit by this ratio of 260 compared with NGO/eLISA. ASTROD-GW has the best sensitivity in the frequency band 100 nHz–1 mHz. The weak phase locking requirement due to longer distance is demonstrated in the laboratory optical activities of JPL. Fig. 2. Bernard Schutz’s slide on sensitivity and Black Hole science. Figure 2 shows a large part of the ASTROD-GW sensitive

8 Asia Pacific Physics Newsletter NEWS

Fig. 4. Comparison of current and planned GW detectors, showing characteristic strain (hc) sensitivity versus frequency along with expected source strengths (Demorest et al., 2009, arXiv: 0902.2968). LIGO, LISA and PTAs occupy complementary parts of the GW spectrum. There is an outstanding gap in the detection band 100 nHz to 10 μHz. The gray strip is the region all current models of MBH-MBH GW backgrounds occupy. ASTROD-GW has the best sensitivity in the 100 nHz – 1 mHz band. The outstanding gap in the detection band 100 nHz to 10 μHz is filled by ASTROD-GW. The

MBH-MBH GW backgrounds of all current models are above the ASTROD-GW sensitivity level. The line in the bottom left corner corresponds to Ωgw = -16 10 inflationary GW background (Ωgw(ƒ) in the figure is decadal density in terms of critical density of the universe defined to be = (1/ρc) (dρgw/dlog ƒ) with ρgw the energy density of the stochastic GW background and ρc the present value of the critical density for closing the universe in .)

region is covered by unresolved binary confusion limit. Masaki Ando from NAOJ described the DECI-hertz Nevertheless, the larger S/N ratios for the more massive interferometer Gravitational wave Observatory (DECIGO) SMBH mergers facilitate luminosity distance determina- project in Japan. DECIGO will have a good sensitivity at tion and the association of electromagnetic counterparts around 0.1–10 Hz band with best sensitivity at 0.1 Hz, for redshift measurements. This will enable a more precise bridging the observation bands between ground-based GW determination of the equation of state for dark energy. detectors and eLISA. Its original and ultimate scientific goal In his talk on ASTROD-GW, Ni from Tsing Hua Univer- is to detect primordial GWs. DECIGO is formed by three sity and Shanghai Normal University showed a diagram drag-free spacecraft, separated by 1,000 km from each other. from the white paper of Demorest et al. (arXiv: 0902.2968) It forms three Fabry-Perot interferometers with 1 m 100 kg with the sensitivities of ASTROD-GW and inflationary GW mirrors and finesse 10. The laser (532 nm) power is 10 W. -16 (with tensor index n = 1, Ωgw = 10 ) lay on it (Fig. 4). This The arm length should be maintained to 20 pm. The three diagram extrapolates Figure 2 to lower frequency and shows stages of DECIGO are DECIGO Pathfinder, pre-DECIGO clearly the potential detectability of MBH-MBH background and (full) DECIGO. The design and the current status of for ASTROD-GW. The detection of primordial (inflationary) its milestone mission DECIGO Pathfinder mission were GWs requires six-S/C configuration and this has a potential presented. Kent Yagi (MSU) gave a presentation on the to probe three orders deeper into the MBH-MBH back- science case for DECIGO Pathfinder and pre-DECIGO. ground (or foreground in this case; the WD binary confusion The most interesting aspect being the direct observations of limit is dominated by this background near 100 nHz). PTA galactic intermediate black hole binaries whose masses and observations will give the level and characteristics of this spins may be estimated with very good accuracy. background and one will be able to analyze the sensitivity of K. G. Arun from CMI gave an overview of various the six-S/C configuration to the primordial GWs. An-Ming ideas which exist in the literature to use gravitational Wu from NSPO (National Space Organization) presented wave observations to perform strong-field tests of General an analysis of deployment of the 3 ASTROD-GW S/C to Relativity. The focus was on the tests that are possible using their science destination. This is crucial for cost estimation the observations of inspiralling compact binaries with the of the mission. ground-based and space-based GW interferometers. The

September 2012, Volume 1 No 2 9 NEWS

Fig. 5 ASTROD I orbit configuration and S/C drawing

important role of space-based GW detectors in performing an overview of the mission concept, experimental setup, precision tests of GR was underlined. Atish Kamble empha- thermal aspects and an update of the mission study with a sized the astrophysical and cosmological importance of design of the spacecraft (Fig. 5). The mission concept is to observing a electromagnetic counterpart to a GW event have a drag-free spacecraft launched directly to solar orbit associated with compact binary merger. The chances of from low earth orbit with Venus assistance during detecting EM counterparts associated with compact binary two encounters to reach the other side of the Sun (relative mergers at radio wavelengths was discussed. Advent of to Earth) in about a year. The ASTROD I S/C will carry a several modern radio-band facilities and surveys coming up telescope, four lasers, two event timers and a clock. Two-way, in the next few years can complement the GW observations two wavelength laser pulse ranging will be used between the of second generation interferometers (AdLIGO, AdVIRGO spacecraft in a solar orbit and deep space laser stations on and KAGRA). Zakharov from ITEP reviewed the effects of Earth, to achieve the ASTROD I goals. In 2011, ASTROD gravitational lensing on GW propagation and detection. The I has been selected as one of the final 14 candidates for the effects would be more important for higher S/N observations Cosmic Vision M3 mission. It is an international project, and limit the precision of observations at high redshifts. More and is envisaged as the first in a series of ASTROD missions. study is crucial for extraction of GW data and interpretation Finally the mission was not selected for the final 4 candi- of GW observations. dates for CV M3 Assessment Study in 2011. Nevertheless, Rajesh Nayak (IISER, Kolkata) presented an overview ASTROD is a very promising concept for a fundamental of the algebraic formalism of Time Delay Interferometry physics space mission and shares some key technologies (TDI) for unequal-arm space based gravitational missions. with other popular space missions like LPF/NGO and Jason He especially presented cases with four beams. Ni talked 2 (T2L2). T2L2 on Jason 2 has been successful. The success on using relativistic ephemeris to numerically simulate the of LPF will verify the crucial drag-free technology needed TDIs for ASTROD-GW and NGO/eLISA, and compare the for ASTROD missions. simulated results of second-generation TDIs together with Ions with larger than 100 MeV/n would charge those of LISA and arm-length doubled NGO/eLISA. All the test masses and induce spurious in drag-free missions. results satisfied their respective requirements. Discharge is necessary to maintain drag-free operations. ASTROD I is a planned interplanetary space mission with Catia Grimani (Univ. Urbino) addressed to this issue and multiple goals. The primary aims are: to test general relativity the placement and design of monitors on the with an improvement in sensitivity of over three orders of LISA Pathfinder mission. She also proposed to place similar magnitude, improving our understanding of gravity and devices on board the eLISA/NGO and ASTROD missions as aiding the development of a new theory; well. These detectors allow us to monitor the integral flux of to measure key solar system parameters with increased energetic particles penetrating mission spacecraft and iner- accuracy, advancing solar physics and our knowledge of tial sensors at any time. She illustrated advantages and limits the solar system; and to measure the time rate of change of these devices for estimating the actual test-mass charging. of the gravitational constant with an order of magnitude In addition, particle detectors on board space interferometers improvement and probing and dark energy can be used to carry out multipoint observations of solar gravitationally. Hanns Selig of ZARM, Bremen presented energetic particles (SEPs) at small and large solar longitudes

10 Asia Pacific Physics Newsletter NEWS at different distances from Earth with minor normalization Chandrayaan-II were also discussed. errors. These measurements will provide important clues on Sreekumar chaired a panel discussion on space-based solar physics and space weather investigations. GW detection. LISA, DECIGO and ASTROD-GW were Clocks have been most precise measuring instruments. the three configurations that were considered. The planned In this Symposium, Philippe Laurent of Observatoire de payloads and the frequency ranges of observations of these Paris talked on Cold Atoms devices to probe the Space Time three missions were compared. LISA Pathfinder is scheduled with high accuracy: ACES space mission and STE-QUEST. for launching in the last quarter of 2014; NGO/eLISA hope- The ACES (Atomic Clock Ensemble in Space) mission fully in 2025-6. DECIGO Pathfinder will be bidding for has first to demonstrate the high performances of a new next JAXA selection in about 2-3 years. ASTROD-GW was generation of space clocks — a cold cesium clock, called proposed in 2009 upon call for proposals of GW mission PHARAO, and an active hydrogen maser to be installed on studies by Chinese Academy of Sciences and is still looking an external pallet of the international space station (ISS). for patrons. There was unanimous agreement that the success With high performance time transfer links to implement of LISA Pathfinder (which will test some of the crucial tech- time and frequency comparisons with Earth based clocks nologies all of these detectors will use) and the first detection with a time stability of 10 ps over ten days and a frequency of GWs by ground-based detectors would really improve the accuracy of 10-16, the main science objectives are testing the funding situation for these missions. There was a general validity of the general relativity with accurate measurements feeling that there was need for international collaboration in of the gravitational red-shift and tests of the stability of the order to achieve the final goals of space based gravitational fundamental constants by comparing various ground based wave detection. clocks. This mission is scheduled to operate from 2015 on. G Srinivasan gave the concluding remarks. He saw LIGO- Based on an improved atomic clock, as compared to ACES, India as a window of opportunity for India to enter into and an atomic interferometer able to test the equivalence contemporary big science. It could attract young people into principle by comparing different test masses, a future science and engineering. He also felt that it was important mission proposal STE-QUEST (Space Time Explorer and that IndIGO joined the eLISA consortium. He said that Quantum Equivalence Principle Space Test) is currently in this project gave a rare opportunity to cultivate a symbiosis the assessment phase in the frame of an M-class mission of between theorists, experimentalists and engineers in India. the cosmic vision plan. It poses challenges to the Indian industry and requires a Over the past two decades measurements of temperature cultural revolution. The most interesting aspect of GW and polarization fluctuations in Cosmic microwave back- detection with space based detectors, to him, was the power ground (CMB) have spearheaded the impressive progress in of these observations to test GR in the very strong field . Tarun Souradeep of IUCAA reviewed the current regime inaccessible till now. He found the prospects of Pulsar status of the field dominated by results from the WMAP Timing Arrays to detect GWs to be very interesting and not CMB mission. He then described the Planck Surveyor satel- foreseen during the initial stages by the Pulsar community. lite (launched in 2009) and the many results it is expected The role of quantum clocks and coherent atoms in detecting to deliver in cosmology. The measurement/constraint on GWs in space were also exciting. He suggested setting up a the ratio of tensor to scalar perturbations will indicate the working group under the joint auspices of IAU, COSPAR magnitude of primordial tensor GWs which will give clues and science academies of various countries interested in of detectability to ASTROD-GW and DECIGO missions. GW detection in space. Biswajit Paul (RRI) gave an overview of the science Invited talks of the ASTROD5 Symposium will be potential of the multi-wavelength satellite ASTROSAT. published in a special issue (January, 2013) of review This satellite will be capable of doing high precision X articles in International Journal of D. The ray timing in the 2-80 keV band with moderate energy ASTROD5 meeting was hosted and financially supported resolution. The possibility of ASTROSAT complementing by the Raman Research Institute, Bangalore. Outstation the GW experiments was also mentioned. A S Kirankumar Student participation was facilitated by travel grants from (Space Applicationss Centre) gave a brief account of the the ASTROD Foundation. payload capabilities of Indian space missions. Starting with ARYABHATTA, the first Indian satellite, ISRO has made a lot of progresses in its payload capabilities. India's recent Lunar mission Chandrayaan-I and upcoming mission

September 2012, Volume 1 No 2 11 NEWS Third International Symposium on Plasma Nanoscience Shuyan Xu Institute of Advanced Studies, Nanyang Technological University and National Institute of Education, Singapore

et in the background of the tropical sun and swaying nanoscale synthesis, processing and device fabrication. coconut trees, the Pulai Desaru Beach Resort was the A gala dinner with cultural music and dance perfor- venue for the iPlasmaNano-III Symposium from 27 mances was held on 28 February 2012. The dinner even SFebruary to 1 March 2012. Delegates were picked up in a provided a relaxed atmosphere for the delegates to dance chartered coach and they arrived at the magnificent tropical on stage. The next evening – Karaoke night - was filled with resort of Pulai Desaru within two hours from Singapore, more music and songs. with a stopover at the Desaru Fruit Farm for sightseeing The contented delegates returned to Singapore on 1 and lunch. More than 80 delegates, including many eminent March enriched with wide knowledge of plasma-related and renowned scientists from 19 countries attended the topics presented at the symposium and rejuvenated by the symposium. resort ambience at Desaru. The four-day programme covered 60 plenary, keynote Before this event, a one-day topical workshop on “Plasma and invited lectures on the most recent developments and Applications in Nanomaterials and Photovoltaic Solar Cells” discoveries in plasma nanosciences, nanofabrication, plasma (PANPSC-2012) was held at the Nanyang Executive Centre, photovoltaics and other emerging topics. The symposium NTU on 26 February 2012. The programme included 10 also included in-depth discussions and opportunities for sessions by local and overseas presenters and concluded collaborations between the scientists, leaders and experts on with a NTU/NIE campus tour, visit to the Plasma Sources fundamental and technological aspects of low-temperature and Applications Centre, Plasma Radiation Laboratory and plasmas, ion beams, lasers and related approaches for Solar Cell Fabrication Facilities.

Local and overseas speakers gathered in Desaru for the iPlasmaNano-III Symposium.

12 Asia Pacific Physics Newsletter RESEARCH HIGHLIGHTS Spin-Orbit Coupled Quantum Gases

Hui Zhai Institute of Advanced Study, Tsinghua University, Beijing, China

pin-orbit coupling is an important effect in many areas of physics, for instance, it plays an important role in determining atomic and nuclei structure and it gives Sbirth to topological insulators. However, for long time spin- orbit coupling was not discussed in the physics of ultracold atomic gases, because there is no spin-orbit coupling for the motion of neutral atoms. Recently, there are many proposals of generating various types of spin-orbit coupling in cold (a) (b) atom systems, and in particular, in 2011, Ian Speilman’s group in NIST has realized one of these proposals experimentally (a) Phase of condensate wave function in the “plane wave phase”; in Rb-87 Bose condensate. These progresses generate a lot (b) Spin density in the “stripe superfluid” phase. of interests and many good results have been published in the last couple years. Spin-orbit coupled quantum gases have now become one of the hottest research directions in After the publication of this review, there are several cold atom physics. This review article reviews most recent latest developments in this direction. The most exciting one theoretical and experimental progresses on this direction. is perhaps the experimental realization of spin-orbit coupled Spin-orbit coupling in cold atom system has a few new Fermi gas, and this is first achieved by the collaboration features. Firstly, previously its effect has only been studied between the experimental group in ShanXi University led in fermionic systems, but now we have a system of spin- by Jing Zhang and our group [Phys. Rev. Lett. 109, 095301 orbit coupled bosons, which has been studied very little (2012)]. This opens up new opportunities toward topological before. One important result is that spin-orbit coupling states in cold atom systems. can lead to a new superfluid phase of bosons called stripe superfluid phase, as predicted by our group in 2010 [Phys. “Spin-Orbit Coupled Quantum Gases”, International Journal Rev. Lett. 105, 160403 (2010)]. Such a superfluid phase also of Modern Physics B 26 (2012) 1230001. spontaneously breaks spatial translation and forms density wave or spin wave order. Secondly, in cold atom system the strength of spin-orbit coupling can be as Hui Zhai is a professor of Institute strong as the Fermi energy. This also leads to many new of Advanced Study, Tsinghua features, for instance, it dramatically enhances the transition University, Beijing, China temperature of fermion-paired superfluid [Phys. Rev. Lett. 107, 195305 (2011)]. These new features are emphasized in this review article.

September 2012, Volume 1 No 2 13 RESEARCH HIGHLIGHTS Highlights from the Asia Pacific Region

Quantum Computation One-Way Quantum Computation with Continuous-Wave Lasers promises to deliver unprecedented efficiency by exploiting the laws of in order to process information in ways fundamentally different from today’s classical computers. As recently as a decade ago Raussendorf and Briegel proposed the one-way quantum computer which differs dramatically from the standard model of quantum computation [1]. Whereas the standard model relies on sequences of quantum logic gates that process Fig. 1: Multimode one-way quantum computation. A quantum entangling qubits, the one-way model implements computations as a gate is teleported onto two inputs. sequence of measurements on an array of highly entangled states; the so-called cluster state. A cluster state is first created as a generic resource, and the algorithms to be computed are states to a four-mode cluster, and verified that after compu- determined by the choice and sequence of measurements, tation the output was an entangled two-mode state. We allowing us to imprint a circuit in real time as the flow of coupled the input states to the cluster via teleportation-based information is directed through the cluster. Bell measurements. Figure 1 shows an abstract illustration We have recently demonstrated one-way quantum of our experiment, where C1;C2;C3;C4 denote the four computing in the optical regime, using as a resource a four- optical modes comprising the resource cluster state. The two mode cluster state of light. Four is the minimum size cluster input states α and β are teleported to modes C2 and C3 via that allows for enough degrees of freedom to implement any the modes C1 and C4. The entanglement from the resource desired operation within the important set of one-mode cluster, in the form of a Cz gate, is teleported onto the two Gaussian operations [2]. The community is input modes α and β. This is the only known demonstration broadly speaking divided in to two camps; those using single to date of a truly quantum gate that entangles independent photons as qubits, and those using continuous-wave laser inputs using continuous-wave clusters. The toolbox we have beams. Our experiments are conducted in the continuous- created allows for universal multimode operations within a wave regime, where we encode information in the frequency Gaussian setting. We are now missing just one final opera- sidebands of optical states, much like FM radio. In order to tion, that of a non-Gaussian nature, and we will have the compute any desired Hamiltonian, no matter the complexity, building blocks for a universal one-way quantum computer. one follows a recipe made by decomposing the Hamiltonian [1] R. Raussendorf and H. J. Briegel, Phys. Rev. Lett. 86, 5188 (2001). into a concatenation of less complex gates [3]. Importantly, [2] R. Ukai et al., Phys. Rev. A. 81, 032315 (2010). any such recipe will include no more than single-mode [3] S. Sefi and P. van Loock, Phys. Rev. Lett. 107, 170501 (2011). [4] R. Ukai et al., Phys. Rev. Lett. 106, 240504 (2011). Gaussian gates, two-mode gates, and non-Gaussian gates. [5] R. Ukai et al., Phys. Rev. Lett. 107, 250501 (2011). In our first demonstration we coupled an input state to the cluster and performed all necessary measurements in order R. Ukai, S. Yokoyama, J.-i. Yoshikawa, P. van Loock and A. Furusawa to satisfy the criteria for universality within the one-mode ‘Demonstration of a Controlled-Phase Gate for Continuous- Gaussian operations [4]. Variable One-Way Quantum Computation’, Phys. Rev. Lett. In our most recent work [5] we have implemented an 107, 250501 (2011) important two-mode gate, the controlled-phase (Cz) gate. This gate provides a link (entanglement) between any two modes it acts on, in the given cluster. We demonstrated this by coupling two independent and uncorrelated vacuum

14 Asia Pacific Physics Newsletter RESEARCH HIGHLIGHTS

Bose-Einstein Condensation in the quasimomentum space) of the swallowtail is largest Swallowtail Band Structure of the near unitarity [Fig. 1(b)]. Superfluid Fermi Gas in an Optical More interestingly, we have found that, along with the Lattice appearance of the swallowtail in the BCS side, there exists a narrow band in the quasiparticle energy spectrum close The role played by interaction in ultracold atomic gases in to the chemical potential and the incompressibility of the optical lattices is an important issue. In the case of Bose- Fermi gas experiences a profound dip, unlike in the BEC Einstein condensates (BECs), the interaction is described side. The emergence of the swallowtail and the dip of the by a nonlinear form with respect to the order parameter incompressibility can be explained as a consequence of the which competes with the periodic potential of the lattice. fact that the chemical potential touches the top of the narrow The interaction energy tends to reshape the sinusoidal band in the quasiparticle spectrum when the swallowtail is band structure into a quadratic-like energy dispersion of on the edge of appearing. the superfluid flow. This reshaping is accompanied by the These results are obtained within a range of parameters appearance of a loop structure at the edge of the Brillouin compatible with current experiments. We have also pointed zone, called “swallowtail”. Swallowtails have a large impact on out that the emergence of the swallowtail could provide a transport properties: A direct consequence of the emergence new way to create a directed motion of the gas. We hope of the swallowtail is a breakdown of Bloch oscillations. Since our study stimulates future experiments aimed to observe Bloch oscillations have various important applications, swallowtails with Fermi gases. such as precision measurements of forces and controlling G. Watanabe, S. Yoon, and F. Dalfovo, the motion of wave packets, a better understanding of the ‘Swallowtail Band Structure of the Superfluid Fermi Gas in swallowtail is useful. an Optical Lattice’, Phys. Rev. Lett. 107, 270404 (2011) The problem of the swallowtail band structure can be even more important in Fermi superfluids, due to the possible implications in superconducting in solids and superfluid in neutron stars. However, unlike Multiferroic Materials the Bose case, little has been studied in this problem so far Origin of the Large Polarization in and a fundamental question whether or not the swallowtail Multiferroic YMnO3 Thin Films exists along the crossover from the Bardeen-Cooper- Multiferroic materials have attracted much interest because Schrieffer (BCS) to BEC states is still open. of their ability to control magnetism by the application of a To solve this problem, we have studied the energy band voltage. This ability is expected to reduce the power required structure of the superfluid flow of ultracold dilute Fermi by electronic devices and to increase their speed. However, gases in an one-dimensional optical lattice along the BCS the number of multiferroic materials discovered so far has to BEC crossover. Using numerical simulations based on been small, and ferromagnetism and ferroelectricity in the Bogoliubov-de Gennes equations, we have shown that, the already discovered materials are often much weaker in each side of the crossover region, the swallowtail appears than the required values for using them as ferromagnets in the Bloch energy band of the superfluid above a critical or ferroelectrics. Hence, it has been inevitable to find novel value of the interaction strength [Fig. 1(a)]. The size (width multiferroic materials. In 2011 we succeeded in fabricating The Formula a YMnO3 multiferroic film that has dielectric polarization exceeding that of conventional multiferroic thin films, and performed x-ray diffraction measurements to investigate the magnetic structure and lattice strain of this film.

The thin film (40 nm) of YMnO3 was grown on a YAlO3 (010) substrate by pulsed-laser deposition. Resonant soft x-ray diffraction experiments were performed on the RESOXS end station at the surface-interface microscopy (SIM) beam line of the Swiss Light Source of the Paul Scherrer Institut, Switzerland. Hard x-ray diffraction expe- riments were performed on beam lines 3A and 4C at the Fig. 1

September 2012, Volume 1 No 2 15 RESEARCH HIGHLIGHTS

Spin configurations of magnetic structures of multiferroic YMnO3 thin films. (a) Spins align antiparallel to each other, resulting in a large lattice strain and large electric polarization.(b) Spins align helically along the viscous resistance, they succeeded in accurately predicting b-axis, resulting in small electric polarization. the dynamics of the blot emanating from a stationary pen and the frontal shape and the final width of the line laid out Photon Factory, KEK, Japan. by a moving pen. We discovered that the spin of Mn ions has two coex- Because paper is made of cellulose fibers, which are isting magnetic structures, namely the cycloidal and E-type a major constituent of cell walls of plants, this study has antiferromagntic (AF) orderings. Below 40K, small electric more profound implications than it first seems. They aim to polarization appears as a result of the cycloidal ordering and better explain how water is delivered from roots of gigantic the periodicity of the cycloidal magnetic structure is incom- trees to leaves more than 100 meters above ground, which mensurate with the crystal lattice. The E-type AF ordering has eluded scientists’ understanding so far. Also functional appears in addition to the cycloidal ordering below 35K. The porous materials that absorb water are increasingly used in periodicity of the E-type AF ordering is commensurate with biomedical fields, which may benefit from this study. the crystal lattice, and the lattice strain due to interactions between ions with parallel spins was found to be the origin of J. Kim, M.-W. Moon, K.-R. Lee, L. Mahadevan and H.-Y. Kim, the large polarization. This understanding of the mechanism ‘Hydrodynamics of Writing with Ink’, Phys. Rev. Lett. 107, 264501 (2011) of the multiferroic behaviors in YMnO3 thin films is expected to support the design of multiferroic materials for practical applications in the future. H. Wadati, J. Okamoto, M. Garganourakis, V. Scagnoli, U. Fractals Staub, Y. Yamasaki, H. Nakao, Y. Murakami, M. Mochizuki, Dynamic Structure Factor of Vibrating M. Nakamura, M. Kawasaki and Y. Tokura, Fractals ‘Origin of the Large Polarization in Multiferroic YMnO3 Thin Films Revealed by Soft- and Hard-X-Ray Diffraction’, Porous materials, proteins, sol-gel branched polymer Phys. Rev. Lett. 108, 047203 (2012) clusters, colloidal aggregates and the spatial organization of chromatin in the nucleus are well known examples of natu- rally occurring fractals. Scattering experiments, in which the Hydrodynamics dynamic structure factor S(k, t) (DSF) is measured, provide an important method for the characterization of fractal Hydrodynamics of Writing with Ink structure and dynamics. Offering simultaneous probing of Although millennia have passed since humans started to correlations in both space and time, DSF measurements write and draw with ink on paper (papyrus in the beginning), have provided invaluable data in various areas of research. the mathematics of writing with ink has been out of the focus In the context of solid fractals, the DSF has been extensively of scientists so far. The team led by Prof. Ho-Young Kim at analyzed on the single phonon level, and in the absence of Seoul National University studied how ink spreads from a any source of friction. As a result, we now have a robust pen onto paper using a minimal pen made of a capillary tube description of the inelastic (Brillouin) scattering from solid which writes on a model of paper, a hydrophilic micropillar fractals. However, due to large fluctuations and friction array. They found that the ink is pulled toward small pores dominated dynamics, this description is not adequate for on paper which is smaller than the pen opening due to capil- the quasi-elastic scattering from low dimensional fractals lary action. No pores, no ink writing, they said, as one can in solutions. An adequate theory, aimed at explaining DSF easily observe by attempting to write on smooth glass plate. measurement taken from the naturally occurring fractals By considering the balance of the capillary and the mentioned above, is therefore lacking.

16 Asia Pacific Physics Newsletter RESEARCH HIGHLIGHTS

stretching exponent ~_ 0.32, which can motivate experiments in this direction. The authors believe that their results can be applied to a variety of other fractal systems as well. S. Reuveni, J. Klafter and R. Granek ‘Dynamic Structure Factor of Vibrating Fractals’, Phys. Rev. Lett. 108, 068101 (2012).

Fundamental Constants Constraining the Fundamental Constants Fractals are characterized by a few broken dimensions, of Physics Through Astronomical among which are: (i) the mass fractal dimension df , that Observations of Rotational Transitions of governs the scaling M(r) ~ rdf of the mass M(r) enclosed Methanol in concentric spheres of radius r, and (ii) the spectral ds−1 The existence of four fundamental forces of nature which are dimension ds that governs the scaling g(ω) ~ ω of the vibrational density of states g(ω) with frequency ω. Fractals the same at all times and places is one of the basic assump- tions on which modern physics is founded. Numerous characterized by ds < 2, such as branched polymers and proteins, are quite common. In such fractals, the generalized careful laboratory experiments conducted on Earth have Landau-Peierls instability principle emerges and determines produced results consistent with this assumption. However, that u¯ ~ N 1/ds −1/2, where N is the number of network beads testing its validity in the early Universe, or at locations and u¯ is the root mean square displacement of a network far-removed from the Earth can only be achieved through bead. This instability principle implies the growth ofu ¯ with astronomical observations. The frequency of a particular the size of the object and, as a by product, opens up a new spectral line depends upon the difference in energy between regime of scattering wavenumbers ku¯>> 1. In this limit, and different electronic, vibrational or rotational quantum states, within a wide window of time, the authors Reuveni, Klafter, which in turn depend upon the specific values of one or and Granek find that S(k, t) decays as a stretched exponential more physical constants (e.g. mass, mass, S(k, t) ~_ S(k)e−(Γkt)v, where the relaxation rate anomalously Planck’s constant). 2/ν Different transitions have varying sensitivity to changes in depends on k, Γk ~ k . The stretched exponential relaxation is a consequence physical constants. The rotational transitions are sensitive to changes in μ = m of the anomalous diffusion of a network bead, with a mean p/mc , the proton-to-electron mass ratio. square displacement evolving as ~ tν. The stretching (and This ratio will change either if the relative strength of the anomalous diffusion) exponent ν depends on the fractal and spectral dimensions, ν = 1−ds/2 in a Rouse-type model where the friction is local, ν = (2−ds)/(2−ds+ds/df ) in a Zimm-type model where friction arises from long ranged hydrodynamic interactions, and ν = 2 − ds for vanishing friction. Among other systems, the theory may be applied to: (i) Proteins, for which a stretched exponential decay has been recently measured by neutron spin-echo, in support of their fractal- like structure; (ii) Chromatin, for which telomer dynamics was shown to follow anomalous subdiffusion with ν ~_ 0.32. Noting that, in such a dense polymer system, hydrodynamics is likely to be screened, this result may be _ interpreted within the Rouse model to yield ds ~ 1.36. This value of ds is remarkably close to that of percolation clusters in 2 < d < 5 dimensions and suggests the presence of DNA crosslinks (e.g. via ligation). According to this result, the DSF of chromatin should decay as a stretched exponential with

September 2012, Volume 1 No 2 17 RESEARCH HIGHLIGHTS

observations which found marginal evidence for changes in |Δμ/μ| at levels above 10-6. Future observations of the methanol absorption in this system with higher signal-to-noise and including additional transitions are expected to achieve an order of magnitude better sensitivity, than that achieved to date.

References : S. P. Ellingsen, M. A. Voronkov, S. L. Breen, 2011, Phys. Rev. Lett. 107, 270801 (2011). S. P. Ellingsen, M. A. Voronkov, S. L. Breen, J. E. J. Lovell, 2012, Astrophys. J. 747, L7 (2012) P. Jansen, L.-H. Xu, I. Kleiner, W. Ubachs, H. L. Bethlem, Phys. Rev. Lett. 106, 100801 (2011) S. A. Levshakov, M. G. Kozlov, D. Reimers, Astrophys. J. 738, 26 (2011) S. Ellingsen, M. Voronkov and S. Breen ‘Practical Limitations on Astrophysical Observations of Methanol to Investigate Variations in the Proton-to-Electron Mass Ratio’, Phys. Rev. Lett. 107, 270801 (2011) electromagnetic and strong-nuclear forces were to vary, or if chameleon-like scalar fields are the mechanism respon- Quantum Dynamics sible for dark-energy. In the first case we would expect to Quantum Dynamics of a Driven be most likely to observe evidence for differences in μ at cosmological distances. For the second case we expect μ to Correlated System Coupled to Phonons show density dependence, hence a different value in the very One of the outstanding contemporary challenges in low densities of interstellar gas, compared to that measured is to understand the dynamics of in the laboratory. interacting quantum systems exposed to an external pertur- Recent theoretical investigations of the methanol bation. Advanced pump and probe techniques with few

(CH3OH) molecule by Jansen et al. (2011) and Levshakov femtosecond time resolution and broadband THz spectros- et al. (2011) have shown that the hindered internal rotation copy were developed to drive the system out of equilibrium exhibited by methanol makes it 1-2 orders of magnitude more sensitive to changes in μ than any other astrophysically observed molecule. This is because unlike most molecules the various transitions of methanol have very different sensitivities to changes in μ. Ellingsen et al. (2011) have used observations of 6.7 and 12.2 GHz methanol masers in Galactic star formation regions to limit changes (3-σ) in the proton-to-electron to |Δμ/μ| < 8.1×10−8 in regions where the density is of order 10-14 kgm-3. The recent detection of methanol absorption in the z=0.89 molecular absorbing galaxy in the PKSB 1830-211 gravitational lens system has allowed the first cosmological constraints on μ from observations of methanol. Ellingsen et al. (2012) have used observations of the absorption from the 12.2 and 60.5 GHz transitions of methanol in this system Figure: Phase diagram in the space of the phonon frequency ω0 and the to constrain (3-σ) changes in μ 7.24 billion years ago to be electron-phonon coupling λ. ηˉ represents a measure of energy flow: if ηˉ >1(<1), the energy flows into phonon (spin) degrees of freedom. Red |Δμ/μ|< 6.3×10−7. This limit is comparable to the best dots denote points in the diagram where the condition ηˉ =1 is fulfilled, Left and right side of the plot correspond to the strong coupling (SC) and previous cosmological constraints on changes in the proton- weak coupling (WC) regime of electron-phonon coupling, respectively. to-electron mass ratio, and in inconsistent with a number of Filled ellipse represents parameters as relevant for cuprates.

18 Asia Pacific Physics Newsletter RESEARCH HIGHLIGHTS and measure its nonequilibrium physical properties. In the systems with competing interactions the most demanding task is to disentangle different elementary excitations arising at comparable energy-time scales. The aim of the Letter is to study a doped strongly corre- lated system coupled to phonons, where the energy gained by the motion of a charge carrier along the field is absorbed by quantum spin and phonon degrees of freedom which are all explicitly included in the model. We study a single charge carrier doped into a two-dimensional (2D) plane within the t-J-Holstein model, which is a prototype model for the description of competing interactions in cuprate supercon- ductors. We address a fundamental, yet unresolved question concerning the interplay between strong correlations and electron-phonon interaction in a driven quantum system far from equilibrium. In the Letter, two important aspects of nonequilibrium carrier dynamics are explored. (i) By the examination of the influence of electron-phonon coupling on the nonlinear Fig. 1. (a) Theoretical spin calculated with three different Hamilto- transport properties of a carrier in the t-J-Holstein model, nians. The two inserts are for the blown-up figures of the low energy parts it is shown that the coupling to phonons decreases carrier to illustrate the effects of the Dzyaloshinskii-Moriya-like term on the spin waves along the Γ-M (left), Γ-K-M and Γ-A (right) directions, respectively. mobility; however, it leads to an enhancement of quasista- (b) Experimental spin waves measured at AMATERAS beamline (circles) tionary current in the regime of negative differential resist- and MERLIN beamline (contour plot) together with the theoretical spin waves (solid line) calculated with J=4.38 meV and J’=0.15 meV: the dashed ance. (ii) By the comparison between the energy absorbed line is for the theoretical spin waves calculated with the Hamiltonian by the spin subsystem and the one absorbed by lattice having the NN interaction alone. Inserts are for the momentum cut at the M and A points. vibrations, it is found that the spin subsystem absorbs the energy from the field more efficiently than the lattice for model parameters fitting cuprate superconductors. K, and this spiral spin structure disappears and becomes a L. Vidmar, J. Bonča, T. Tohyama and S. Maekawa simple G-type antiferromagnetic structure when prepared in ‘Quantum Dynamics of a Driven Correlated System Coupled thin film forms. Despite the numerous reports of the unusual phenomena found in BiFeO , the underlying microscopic to Phonons’, Phys. Rev. Lett. 107, 246404 (2011) 3 spin Hamiltonian is not well established yet. Surely, under- standing the microscopic magnetic interaction should be a proper starting point for fundamental discussions about its Multiferroic Materials magnetic properties. Spin Wave Measurements over the Full A main reason for this absence of the spin wave measure- ment is that it is quite challenging to grow large single crystals Brillouin Zone of Multiferroic BiFeO3 as well as several experimental and technical difficulties. Multiferroic materials, where the magnetic order and We have addressed this problem by growing several high ferroelectric polarization coexist, are one of the most quality single crystals and making an assembly of ten crystals sought-after topics in the condensed matter physics. The co-aligned with a total mass of 1.9 g. Using these samples, current intense interest on such materials is driven not only by the intellectual desire but also by its immense potential we have carried out inelastic neutron scattering experiments for future applications. with two time-of-flight spectrometers: one is AMATERAS at the J-PARC, Japan and another MERLIN at the ISIS, UK. BiFeO3 is arguably one of the most interesting multifer- roic compounds, with both ferroelectric and magnetic In order to analyze the data, we started with a minimal transitions above room temperature and very large polariza- Heisenberg Hamiltonian only with the nearest neighbor tion value, ~100 μC/m2. In addition, an incommensurate interaction and then extended it, when necessary to structure is formed with an extremely long period of 620 explain the measured dispersion curve, by including the Å when it undergoes an antiferromagnetic ordering at 650 next nearest neighbor interaction and a Dzyaloshinskii- September 2012, Volume 1 No 2 19 RESEARCH HIGHLIGHTS

Moriya-like term as the following model Hamiltonian: it difficult to realize scalable qubits. For the implementation H=J S ∙S +J' S ∙S –D∙ S ×S , of large-size quantum gates an array of coupled molecular ∑ i j ∑ i j ∑ i i+δ NN NNN i clusters should be embedded in a microwave cavity. When for the magnetic unit cell of the G-type structure. The third the molecular magnets are integrated into semiconducting term describes a Dzyaloshinskii-Moriya-like interaction nanostructures, there might appear additional decoherence with i+δ representing the next nearest neighbor of site i channels. Thus, it is necessary to understand possible deco- along the [1 1 0] direction. By carefully examining the data, herence sources in such a hybrid material. we succeeded, for the first time, in measuring the full spin In our study, freestanding nanoporous silicon (NS) was waves of BiFeO and determined the two most important 3 exploited as a host of molecular magnets. The spin triangle exchange parameters, which are the nearest and next nearest clusters {Cu3-X}(X=As,Sb) were successfully impregnated neighbor interactions: J=4.38 and J’=0.15 meV, respectively. into NS by electrochemical etching methods (Left panel of Surprisingly enough, a simple spin Hamiltonian with these Figure 1). We prepared for samples with different symmetries two exchange interactions explains the measured spin waves. and environments: (i) as-grown {Cu3-X} crystals, (ii) deuter- We further estimated an effective Dzyaloshinskii-Moriya ated {Cu3-X} crystal, (iii) {Cu3-X}:NS with two different interaction: D=0.107 meV for the incommensurate magnetic concentrations, and (iv) {Cu3-X} impregnated in a metallic structure. Our results ought to be the key to deeper under- NS. High-field/high-frequency pulsed electron paramag- standing of the physical properties of BiFeO . 3 netic resonance (EPR) measurements were performed on

J. Jeong, E. A. Goremychkin, T. Guidi, K. Nakajima, G. S. the {Cu3-X}:NS hybrid material. Jeon, S.-A. Kim, S. Furukawa, Y. B. Kim, S, Lee, V. Kiryukhin, We demonstrate a coherent manipulation of the electron S-W. Cheong and J.-G. Park spin in the {Cu3-As}:NS for temperatures below 2.2 K at ‘Spin Wave Measurements over the Full Brillouin Zone of H=9.43 T (Left panel of Figure 1). The observed Rabi oscil- Multiferroic BiFeO ’, Phys. Rev. Lett. 108, 077202 (2012) 3 lations (a NOT gate) correspond to coherent oscillation of the electron spin between the two states of the ST=1/2 levels.

The spin coherence time is measured to be 2T =1066 ns at Condensed Matter 1.5 K, yielding a single-qubit figure of merit of one hundred. Coherent Manipulation of Electron The temperature dependence of the spin-spin relaxation

rate (1/T2) shows that dipolar interactions and hyperfine Spins in the {Cu3} Spin Triangle Complex Impregnated in Nanoporous Silicon couplings are not the major decoherence paths due to a spin polarization under a high magnetic field (Right panel Decoherence remains a main obstacle for employing mole- of Figure 1). Further, we find no significant interactions cular magnets in quantum devices and computers. Although between conducting electrons of a metallic NS and the core a coherent manipulation of electron spins has been reported electron spins of the {Cu3-X} molecule. This indicates that in several molecular magnets (for example, {Cr7Ni}, {V15}, the molecules can be incorporated into silicon nanodevices

{Fe4}, and {Fe8}), most of the works have been performed in without causing a substantial spin decoherence. The most a frozen solution to suppress spin decoherence. This makes drastic change in 1/T2 occurs by replacing the heteroatom As by Sb, which controls a degree of isosceles distortions. A different degree of isosceles distortions, that is, a different molecular symmetry leads to a different mixing degree between states of equal spin but different . This gives strong influence on a relaxation rate of the transition between the chiral states. Thus, a spin memory time can be increased through molecule symmetry engineering. To conclude, the

{Cu3-X}:NS spin triangle complex offers new avenues for a spin qubit methodology. K.-Y. Choi, Z. Wang, H. Nojiri, J. van Tol, P. Kumar, P. Figure 1 (Left panel) Rabi oscillations of {Cu3-As}:NS observed for temperatures below 2.2 K at H=9.43 T. Inset: A sketch of a single NS Lemmens, B. S. Bassil, U. Kortz, and N. S. Dalal layer enclosing {Cu -X} molecular clusters. (Right panel) Temperature 3 ‘Coherent Manipulation of Electron Spins in the {Cu3} Spin dependence of a spin-spin relaxation rate of {Cu3-X}:NS with different environments. Inset: Decay of the integrated Hahn echo area as a func- Triangle Complex Impregnated in Nanoporous Silicon’, Phys. tion of delay time recorded for {Cu -As} crystal at T=1.5 K and H=7.63 T 3 Rev. Lett. 108, 067206 (2012) 20 Asia Pacific Physics Newsletter RESEARCH HIGHLIGHTS

Superfluid critical point (QCP). This suppressed superfluidity and the Suppression of the Berezinskii-Kosterlitz- existence of QCP are the manifestation of the strong correla- Thouless Transition and Quantum tion in the films under high pressure. Since the bulk freezing pressure is 2.5 MPa in 4He, it is Criticality in 4He Films at High Pressures intriguing to elucidate the details of the superfluid — normal Superfluid transition of the 4He films has been studied fluid – solid phase diagram in the vicinity of QCP. Effect of extensively and is now established as the topological transi- the disorder on QCP is also an interesting issue. tion called Berezinskii-Kosterlitz-Thouless (BKT) transition. Stimulated by the experimental realization of the The coherence of the system is established by formation of 2-dimensional ultra-cold atomic gases in optical lattices quantum vortex and anti-vortex pairs below the transition where particle correlation can be tuned by the lattice temperature. BKT transition of the 4He films, however, has potential, theories have been proposed about the strongly been studied only at the saturated vapor pressure so far, correlated 2-dimensional Bose system. There have been, where particle correlation is weak and the strong correlation however, no experimentally accessible continuum systems effect on BKT transition cannot be examined. which clearly show the correlation effect. In this sense, Researchers at Tokyo Institute of Technology succeeded their discovery of the QCP in the 4He films, where the in creating the strongly correlated 4He films by pressurizing strong correlation is apparently due to the inter-particle them between a high-frequency oscillator wall and the interactions, is complementary to the atomic gas system bulk 3He liquid, the result of which is published in Physical and provides a new playground for studying the strong Review Letters 108, 025302 (2012). They found that the correlation effect on 2 dimensional Bose fluids. surface specularity or the boundary condition of the 3He S. Murakawa, M. Wasai, K. Akiyama, Y. Wada, Y. Tamura, R. quasiparticles scattered at the 4He surface is sensitively Nomura, and Y. Okuda dependent on whether the 4He film is superfluid or not. ‘Strong Suppression of the Kosterlitz-Thouless Transition The specularity measured by the oscillator response clearly in a 4He Film under High Pressure’, Phys. Rev. Lett. 108, showed that the films undergo a superfluid transition below 025302 (2012) a particular temperature depending on the film thickness and the applied pressure. The frequency dependence of the superfluid transition temperature is well described by Superstring Theory the dynamic BKT transition theory, providing evidence that superfluid transition of the 4He films is really the BKT Expanding (3+1)-Dimensional Universe transition even under the high-pressure liquid 3He. The BKT from a Lorentzian Matrix Model for transition temperature is strongly suppressed from the one Superstring Theory in (9+1) Dimensions at the saturated vapor pressure; it decreases linearly with The mechanism that explains why our universe was born the applied pressure. The transition temperature decreases with 3 dimensions: a 40-year-old puzzle of superstring theory to zero at 2.75 MPa, indicating the existence of the quantum solved by supercomputer. A group of three researchers from KEK, Shizuoka Univer- sity and Osaka University has for the first time revealed the way our universe was born with 3 spatial dimensions from 10-dimensional superstring theory in which space- time has 9 spatial directions and 1 temporal direction. This result was obtained by numerical simulation on a supercomputer. According to cosmology, the universe origi- nated in an explosion from an invisibly tiny point. This theory is strongly supported by observation of the cosmic microwave background and the relative abundance of elements. However, a situation in which the whole universe

Figure: Pressure dependence of the BKT transition temperature of 4He is a tiny point exceeds the reach of Einstein’s general theory films of several thicknesses. of relativity, and for that reason it has not been possible to

September 2012, Volume 1 No 2 21 RESEARCH HIGHLIGHTS

9 spatial dimensions at the beginning, but only 3 of these time underwent expansion at some point in time. Expanding 3D space It is almost 40 years since superstring theory was proposed as the , extending the general theory of relativity to the scale of elementary particles. However, its validity and its usefulness remained unclear due to the difficulty of performing actual calculations. The newly 6D space remaining small obtained solution to the space-time dimensionality puzzle strongly supports the validity of the theory. Furthermore, Birth of Universe the establishment of a new method to analyze superstring theory using computers opens up the possibility of applying Small 9D space this theory to various problems. For instance, it should now be possible to provide a theoretical understanding of the inflation that is believed to have taken place in the early universe, and also the accelerating expansion of the universe, whose discovery earned the this year. It is expected that superstring theory will develop further and play an important role in solving such puzzles in particle physics as the existence of the dark matter that is suggested by cosmological observations, and the Higgs particle, which is expected to be discovered by LHC experiments. S.-W. Kim, J. Nishimura and A. Tsuchiya ‘Expanding (3+1)-Dimensional Universe from a Lorentzian Matrix Model for Superstring Theory in (9+1) Dimensions’, The extents in 9 directions extents The Phys. Rev. Lett. 108, 011601 (2012) Time clarify how the universe actually originated. In superstring Neutrino Mixing theory, which is considered to be the “theory of everything”, Phenomenological Support for Residual all the elementary particles are represented as various oscil- Z 2 Symmetries in Neutrino Mixing lation modes of very tiny strings. Among those oscillation Residual symmetry can serve as an effective theory for flavor modes, there is one that corresponds to a particle that mixing. For Majorana , it consists of just three Z mediates gravity, and thus the general theory of relativity can 2 groups. They can be denoted as Zµτ , and Z¯ s or the related be naturally extended to the scale of elementary particles. 2 2 Zs , corresponding to good zeroth-order approximations for Therefore, it is expected that superstring theory allows the 2 the three mixing angles. The Zµτ invariance of the neutrino investigation of the birth of the universe. However, actual 2 mass matrix determines the reactor angle θ (≡ θ ) and the calculation has been intractable because the interaction x 13 atmospheric angle θ (≡ θ ) to be zero and 45° respectively between strings is strong, so all investigation thus far has a 23 while Zs and Z¯ s depend on the solar angle θ (≡ θ ). been restricted to discussing various models or scenarios. 2 2 s 12 Recent T2K, MINOS, and Double Chooz experiments In particular, superstring theory predicts a space with 9 show that θ does not vanish. Hence, Zµτ is violated and only dimensions, which poses the big puzzle of how this can be x 2 Zs or Z¯ s are left. These partial residual symmetries provide consistent with the 3-dimensional space that we live in. 2 2 very interesting phenomenological predictions for the A group of 3 researchers, Jun Nishimura (associate neutrino mixing parameters. They induce a direct and unique professor at KEK), Asato Tsuchiya (associate professor at relation expressing θ in terms of the other two mixing angles, Shizuoka University) and Sang-Woo Kim (project researcher x θ and θ , and the Dirac CP phase δ of the form at Osaka University) has succeeded in simulating the birth of s a D the universe, using a supercomputer for calculations based on superstring theory. This showed that the universe had

22 Asia Pacific Physics Newsletter Phenomenological Support for Residual Z2 Symmetries in Neutrino Mixing

Shao-Feng Ge1,∗, Duane A. Dicus2,†, and Wayne W. Repko3,‡ 1Institute of Modern Physics and Center for High Energy Physics, Tsinghua University, Beijing 100084, China 2Physics Department, University of Texas, Austin, TX 78712 3Department of Physics and Astronomy, Michigan State University, East Lansing MI 48824 (Dated: February 29, 2012)

Residual symmetry can serve as an effective theory for flavor mixing. For MajoranaRESEARCH neutrinos, HIGHLIGHTS it consists of µτ s s just three Z2 groups. They can be denoted as Z2 , and Z2 or the related Z2, corresponding to good zeroth-order µτ approximations for the three mixing angles. The Z2 invariance of the neutrino mass matrix determines the reactor s s where p = +1/−1 for Z /Z¯ . Using this relation and ◦ s s angle θx(≡ θ13) and the atmospheric2 2 angle θa(≡ θ23) to be zero and 45 respectively while Z2 and Z2 depend on the a uniform distribution≡ of δ , Z s predicts a θ likelihood solar angle θs( θ12). D 2 x Superconductivity Induced by Phenomenological Support for Residual Z2 Symmetries in Neutrino Mixing distribution centered around 3° ~ 6° with an uncertainty of µτ Recent T2K, MINOS, and Double Chooz experiments show that θx does not vanish. Hence, Z2 is violated and s Longitudinal Ferromagnetic Fluctuations 1,∗ 22°,† to 40 ass shown in the Fig.3 1(a),,‡ while the results from Zs Shao-Feng Ge , Duane A. Dicus only, andZ2 Wayneor Z2 W.are left.Repko These partial residual symmetries provide very interesting phenomenological predictions for 1 in UCoGe Institute of Modern Physics and Center for High Energy Physiarethe approximatelycs, neutrino Tsinghua mixing University,a factor parameters. of two Beijing larger. 100084, They Either induce China result a fits direct the and unique relation expressing θx in terms of the other two 2 Physics Department, University ofT2K,mixing Texas, MINOS Austin, angles, and TXθ Doubles and 78712θ aChooz, and themeasurements. Dirac CP phase δD of theAfter form the discovery of superconductivity in the ferromagnetic 3Department of Physics and Astronomy, Michigan State University, East Lansing MI 48824 Alternately, solving the equation for δD results in a peak 2 UGe under pressure, the relation between ferromagnetism sin θ = p ± cos2 δ + cot 2θ −2cos δ tan 2θ (tan θ )p , (Dated: February 29, 2012) x  D a D a s at ±74°(±106°) for Zs or ±123°(±57°) for Z2 , as illustrated and superconductivity has attracted much interest. From the s s s inwhere the Fig.p 1(b).= +1/ This−1 is for consistentZ2/Z2. with Using the thislatest relation global fits. and atheoretical uniform distribution point of view, of inδ anD, itinerantZ2 predicts FM superconductor a θx likelihood Thesedistribution model-independent centered around predictions 3◦ ∼ 6 ◦arewith quite an robust uncertainty and with of 2◦ theto 4presence◦ as shown of a in large the energy left hand splitting figure between below, while the Residual symmetry can serve as an effective theory for flavor mixing. ForZ Majoranas neutrinos, it consists of µτ s theirthe consistency results froms with2 are data approximately strongly supports a factor the ofpartial two larger. majority Either and result minority fits t spinhe T2K, Fermi MINOS surfaces, and exotic Double spin-triplet Chooz just three Z2 groups. They can be denoted as Z2 , and Z2 or the related Z2, corresponding to good zeroth-order Zµτ measurements. superconductivity is anticipated, in which pairing is between approximations for the three mixing angles. The 2 invarianceresidual of the symmetry neutrino Zs mass or Z matrix2. determines the reactor s s ◦ ◦ s ◦ ◦ Alternately,◦ solving the equations for δD results in a peak at ±74 (±106 ) for Z2 or ±123 (±57 ) for Z2, as angle θx(≡ θ13) and the atmospheric angle θa(≡ θ23) to be zero andIn addition, 45 respectively we also predict while aZ distribution2 and Z2 depend for the onJarlskog the parallel spins within each spin Fermi surface. It is also argued ≡ illustrated in the right hand figure below. This is consistent with the latest global fits. These model-independent solar angle θs( θ12). leptonic invariant J that can be tested by measurements at that critical FM fluctuations near a quantum phase transitions ν Zs Z predictions are quite robust and theirµτ consistency with data strongly supports the partial residual symmetry 2 or 2. Recent T2K, MINOS, and Double Chooz experiments showT2K that andθx NOVA.does not vanish. Hence, Z2 is violated and could mediate spin-triplet superconductivity [1]. However, In addition, we also predict a distribution for the Jarlskog leptonic invariant Jν that can be tested by measurements Zs Zs only 2 or 2 are left. These partial residual symmetries provideatAll T2K very the andabove interesting NO resultsνA. phenomenological are also true for Dirac predictions neutrinos. for there have been no experimental results indicating a clear the neutrino mixing parameters. They induce a direct and unique relation expressing θx in terms of the other two relationship between FM fluctuations and superconductivity. CP All the above results are also true for Dirac neutrinos. mixing angles, θs and θa, and the Dirac phase δD of the form Among the FM superconductors discovered so far, 0.20 �150 ° �100 ° �50 ° 0 2 s 2 p  ∆ �  Π ± −  Z2 D 0,2 UCoGe [2] is one of the most readily explored experimentally, sin θx = p cos δD + cot 2θa cos δD tan 2θa(tan θs) ,     ∆ � 0 0.012 s  D 0 Z2   ∆ � 0 because of its high superconducting (SC) transitions tempe-   D 60  s  Z2 − Zs Z 0.15 Zs ∆ � 700 0.010 where p = +1/ 1 for 2/ 2. Using this relation and a uniform distribution of δD, 2 predicts a θxD likelihood  s ∆ �  Π rature (TSC ~ 0.7 K) and low Curie temperature (TCurie ~ Z2 D 0,2 ◦ ∼ ◦ ◦ ◦  distribution centered around 3 6 with an uncertainty of 2 tox 4 as shown in the left  hand figure below, while Θ 2.5 K) atD 0.008 ambient pressure. Microscopic measurements have s d  d ∆ Z  x  the results from 2 are approximately a factor of two larger. Either result fits the T2K, MINOS   and Double Chooz  Θ 0.10   D     shown ∆ that superconductivity  occurs within the FM region,   0.006  dP      measurements.      dP              s resulting in microscopic coexistence of ferromagnetism and ◦ ◦  s  ◦  ◦          δ ± ±  Z  ±  ± Z 0.004   Alternately, solving the equation for D results in a peak at 74 ( 106 ) for  2 or 123( 57 ) for 2, as  0.05             superconductivity [3]. The magnetization has Ising-like                  illustrated in the right hand figure below. This is consistent with the latest global  fits. These model-independent      0.002      s       s anisotropy with the easy axis parallel to the c axis [4, 5],      Z Z           predictions are quite robust and their consistency with data strongly supports   the partial residual symmetry  2 or  2.                                0.00� � and direction-dependent0.000 nuclear-spin lattice relaxation rate In addition, we also predict a distribution for the Jarlskog leptonic invariant10° 5°Jν that0° can be5° tested10° by measurements15° 20° �180 ° �135 ° �90 ° �45 ° 0 Θ ∆ at T2K and NOνA. x (1/T1) measurements on a singleD crystalline sample have All the above results are also true for Dirac neutrinos. (a) revealed the magnetic fluctuations in UCoGe to be Ising-type FIG. 1: Predictions for θx and δD. There are mirrorFM distributions ones along the as cδD axis→− (longitudinalδD and δD → FMπ spin− δD fluctuations). 0.20 �150 ° �100 ° �50 ° 0 s  ∆ �  Π  Z2 D 0,2  [6]. Enigmatic anisotropic behaviors of superconductivity   ∆ � 0 0.012 s D 0 Z2   ∆ � 0 s   D 60  were also reported by studies of the SC upper critical field  Z2 0.15 ∆ � 0 0.010  D 70  s ∆ �  Π Z2 D 0,2 (H ) and its angle dependence along each crystalline axis [4,  C2 x  ∗ ElectronicD 0.008 address: [email protected] d Θ  ∆ 5]: superconductivity survives far beyond the Pauli-limiting d  † x    Electronic address: [email protected] Θ 0.10     D   ‡ ∆    0.006  field along the a and b axes, whereas H of the c direction dP    Electronic address: [email protected] C2      dP                    is as small as 0.5 T. In addition, a steep angle dependence of             0.004         0.05                        H was reported when the field was tilted slightly from the        C2          0.002                             a axis to the c axis. The observed characteristic H behavior,          C2                              0.00� � 0.000 10° 5° 0° 5° 10° 15° 20° �180 ° �135 ° �90 ° �45 ° 0 in addition to the anisotropic magnetic behaviors, is one of Θ ∆ x D mysterious features of UCoGe, whose origin would link with (b) the mechanism of the superconductivity. θ δ δ →−δ δ → π − δ FIG. 1: Predictions for x and D. There are mirror distributions as D D and D D. From precise angle-resolved 1/T and H measurement, Fig. 1: Predictions for θx and θD. There are mirror distributions as δD → −δD 1 C2 and → π − . δD δD we observed strong suppression of the longitudinal FM fluctuations by the magnetic field along the c axis C(H ), and found that HC is a tuning parameter of FM fluctuations. ∗ Electronic address: [email protected] † We also found that the superconductivity is observed in the Electronic address: [email protected] S.-F. Ge, D. A. Dicus and W. W. Repko ‡ Electronic address: [email protected] limited magnetic field region where the longitudinal FM ‘Residual Symmetries for Neutrino Mixing with a Large θ 13 spin fluctuations are active (Fig. 1). These results combined and Nearly Maximal δ ’, Phys. Rev. Lett. 108, 041801 (2012) D with model calculations (Fig. 2) strongly suggest that the

September 2012, Volume 1 No 2 23 RESEARCH HIGHLIGHTS

[1] D. Fay and J. Appel, Phys. Rev. B 22, 3173 (1980). [2] N. T. Huy et al., Phys. Rev. Lett. 99, 067006 (2007). [3] T. Ohta et al., J. Phys. Soc. Jpn. 79, 023707 (2010). [4] N. T. Huy et al., Phys. Rev. Lett. 100, 077002 (2008). [5] D. Aoki et al., J. Phys. Soc. Jpn. 78, 113709 (2009). [6] Y. Ihara et al., Phys. Rev. Lett. 105, 206403 (2010). [7] V. P. Mineev, Phys. Rev. B 66, 134504 (2002). T. Hattori, Y. Ihara, Y. Nakai, K. Ishida, Y. Tada, S. Fujimoto, N. Kawakami, E. Osaki, K. Deguchi, N. K. Sato, and I. Satoh ‘Superconductivity Induced by Longitudinal Ferromagnetic Fluctuations in UCoGe’, Phys. Rev. Lett. 108, 066403 (2012)

Magnetoelectric Effect Magnetoelectric Effect in an XY-like Spin

Glass System NixMn1-xTiO3 A magnetoelectric (ME) effect, i.e., magnetic control of electric polarization or electric control of magnetization, Fig.1 Hc dependence of magnetic fluctuations along c axis ‹(δHc)2› at 1.7 c c 2 K. Hc2 data are also plotted against H = Hc2 sinθ Inset: plot of ‹(δH ) › has received great interest in recent years because of their against | Hc |. The relation of ‹(δHc)2›/ ( Hc )1/2 is shown by dashed lines in the main panel. potential use for future electronics. Usually, the ME effect can exist in crystals with “ordered” spin structures, and then most experimental studies on the ME effect have been done for materials showing “long-range magnetic orders”. However, recent theoretical studies suggest that some multi- spin variables should play an important role in inducing magnetoelectricity. In this paper, Yamaguchi and coworkers offer a new approach to studying magnetically-disordered systems by means of the ME effect due to an alignment of a multi-spin variable, “toroidal moment”.

t

spinSi

∝ × t Σi ri Si toroidal moment Fig.1 )

2 -H H 2 P P C/m + μ

Fig.2 Angular dependence of Hc2 in the ac plane, which is determined ( H XY 1 by the onset of Meissner signal (denoted by the arrows in the Inset). c2 P data reported by D. Aoki et al. are also plotted [5]. The red curve in the 0 main panel is the calculation of the angle dependence of Hc2 based on the spin-triplet A state [7] by taking account the field dependence of the larization

Ising FM fluctuations shown in the inset of Fig.1. o -1 Figure 1 H -H -P -P -2 + Electricp C longitudinal FM spin fluctuations tuned by H induce the -10 -5 0 5 10 unique spin-triplet superconductivity in UCoGe, concomi- Magneticfield μ0H (T) Fig. 2 tantly resolving the above-mentioned puzzle of Hc2. 24 Asia Pacific Physics Newsletter

Figure 2 RESEARCH HIGHLIGHTS

The toroidal moment t is described as the outer product or strong system-environment coupling, the PS are known of the displacement of magnetic ions from the center posi- to be the energy eigenstates of the system Hamiltonian tion ri and their spins Si; i.e., t ∝ Σi ri × Si, as illustrated in or the eigenstates of the system-environment interaction Fig. 1. The sign of t changes under time reversal and space Hamiltonian. While, little has been known about the possible inversion operation, and ME effects in several compounds existence of PS for a generic system-environment coupling such as Ga2-xFexO3 have been discussed in terms of the (i.e. not commutable with system’s self-Hamiltonian) of toroidal ordering. Theoretically, this multi-spin variable intermediate strength. can be nonzero even in the absence of long-range magnetic We work with a computationally intuitive definition of order. Thus, it is possible that ME materials are found in PS. That is, if after a certain period the eigenstates of the magnetically-disordered systems, though most of previous RDM are found to evolve closely around a fixed basis set, experimental studies on magnetoelectricity have been done then this fixed set of states can be defined as the PS, at least on materials showing long-range magnetic orders. approximately. Consistent with this picture, the off-diagonal To demonstrate this hypothesis, Yamaguchi and elements of the RDM in the PS representation must be small coworkers performed detailed measurements of ME proper- when compared with the difference of its diagonal elements. ties in ilmenite-type NixMn1-xTiO3, which is known as an These preliminaries also make it clear that even a stationary XY-like “spin glass” system, i.e. one of typical magnetically- RDM does not necessarily mean the existence of PS. disordered systems. In XY-like SG systems, noncollinear spin To reflect the fact that typically a small system S is not configurations confined within the XY plane are possible directly coupled to the whole of its environment E, we let S and might align the ME active multi-spin variables such as be directly coupled to a small component A of E, and then toroidal moment. In fact, they found “anti-symmetric ME let A be further coupled to the rest part B of E, with E=A+B. effects” in samples showing XY-like SG character (Fig. 2). For convenience, both S and A are assumed to be two-level This is the first observation of the ME effect in spin-glass systems. The B part of E is simulated by a quantum kicked systems having a centrosymmetric crystal structure. They rotor on a torus with only 1 degree of freedom, whose discuss the origin of the ME effect in terms of an align- classical limit is fully chaotic.The irregular motion of B due ment of the toroidal moment, and found that the toroidal to quantum chaos, instead of many noninteracting degrees scenario well explains most of the experimental observa- of freedom of a thermal bath, is responsible for decoherence tions. Their results suggest that studies of ME properties in in S. Via this simple dynamical model, it is shown that even magnetically-disordered system provide an opportunity to for intermediate system-environment coupling, approximate study multi-spin variables by their separation from ordering PS may still emerge from the coherent quantum dynamics of of spins. Furthermore, it is not too much to say that the the whole system in the absence of any thermal averaging. contents of this paper provide a new approach to the study The found PS can also continuously deform to expected of magnetically-disordered systems. limits for weak or strong system-environment coupling. Computational results are also qualitatively explained. The Y. Yamaguchi, T. Nakano, Y. Nozue and T. Kimura findings should be useful towards further understanding of ‘Magnetoelectric Effect in an XY-like Spin Glass System decoherence and quantum thermalization processes. NixMn1-xTiO3’, Phys. Rev. Lett. 108, 057203 (2012) W. Wa n g , L. He and J. Gong ‘Preferred States of Decoherence under Intermediate System- Decoherence Environment Coupling’, Phys. Rev. Lett. 108, 070403 (2012) Preferred States of Decoherence under Intermediate System-Environment Quantum Optics Coupling Two Photons at Once from a Single Decoherence may rapidly reduce a coherent superposition Quantum Dot state of a system to an incoherent mixture. During this process the environment singles out special basis states, A single artificial atom – which usually emits one photon at often called “Preferred (pointer) States” (PS). That is, in a time – has been forced to emit two photons at once. the PS representation the reduced density matrix (RDM) According to the quantum theory of radiation, the of the system becomes diagonal as time evolves. For weak fundamental optical process for an excited atom interacting

September 2012, Volume 1 No 2 25 RESEARCH HIGHLIGHTS with the vacuum field fluctuations is single photon emission. electromotive force to the time derivative of a magnetic flux. The atom can also emit two photons simultaneously, as a Involved is a coupling to the electrical charge of electrons. higher order process. However, it rarely happens under the Recently, a motive force of spin origin, i.e. a “spinmotive interaction with the faint vacuum field. force” (SMF)[1], has attracted much attention. An SMF reflects the conversion of the magnetic energy of a ferro- magnet into the electrical energy of the conduction electrons via their mutual exchange interaction. An SMF reflects the spin of electrons in an essential manner. It is a new concept relevant to spintronic devices[2,3]. The continuous generation of a dc SMF has not been demonstrated. In order to generate any SMF, it is required that the magnetization depends both on the time and space[4,5]. The recent experimental realizations of such forces involve domain wall motion[6,7], or electron transport through ferromagnetic nanoparticles[8]. The magnetization motion and hence the SMF are, by their nature, transient. For application to realistic devices, a continuous generation of a dc SMF is absolutely indispensable.

This effect has been observed in gaseous atoms; but to implement practical devices, it is necessary to develop solid state quantum emitters, where no previous workers were able to observe this vanishing rare process. Ota and co-workers dramatically strengthened the vacuum field around a semiconductor quantum dot, an artificial atom, using a photonic crystal nanoresonator. This nanoresonator, which is less than 1/100 the size of a human hair, can confine photons to this region, dramatically enhancing the vacuum field while maintaining a very high cavity quality factor (exceeding 50,000). This enhanced vacuum field inspires the quantum dot to emit twin photons at once, rather than a single photon. A theoretical calculation using a master equation approach strongly supported the experimental observations. Yamane et al. have demonstrated both by experiment and This work will open the door to new types of “entangled” theory the continuous generation of such a dc SMF[9]. The photon pair sources in the solid state, and form a building above figure shows a schematic illustration of the system, a block for new kinds of semiconductor lasers, “two-photon Ni81Fe19 microstructure composed of a large pad connected lasers”. to an array of wires. That the magnetic field for ferromagnetic resonance (FMR) depends on the sample shape is textbook Y. Ota, S. Iwamoto, N. Kumagai and Y. Arakawa physics. In a highly asymmetrical ferromagnetic thin film, ‘Spontaneous Two-Photon Emission from a Single Quantum such as this “comb” structure, the FMR of the pad and the D o t ’, Phys. Rev. Lett. 107, 233602 (2011) wires can be excited independently. As illustrated, the pad can resonate while the wires do not, this leading to the time and spatial dependence of the magnetization associated with the appearance of a dc SMF. When either of the pad, Continuous Generation of Spinmotive or wire, is excited, a dc SMF is generated continuously. The Force in a Patterned Ferromagnetic Film experimental results are fully consistent with the theoretical predictions for such a motive force, lending strong support In classical electrodynamics, Faraday’s law equates the for this concept.

26 Asia Pacific Physics Newsletter RESEARCH HIGHLIGHTS

[1] S. E. Barnes and S. Maekawa, Phys. Rev. Lett. 98, 246601 (2007). parameter does not affect the temperature of black hole radia- [2] S. E. Barnes et al., Appl. Phys. Lett. 89, 122507 (2006). tion! However, the value of black hole computed [3] Y. Yamane et al., Appl. Phys. Exp. 4, 093003 (2011). [4] G. E. Volovik, J. Phys. C 20, L 83 (1987). using the fundamental discreteness of the area spectrum [5] Y. Yamane et al., J. Appl. Phys. 109, 07C735 (2011). strongly depends on the Immirzi parameter due to its role in [6] S. A. Yang et al., Phys. Rev. Lett. 102, 067201 (2009). modulating the structure of area jumps. In fact one can show [7] M. Hayashi et al., to appear in Phys. Rev. Lett. that entropy is given by S = f (γ)A/(4ℓ2) for some function f [8] P. N. Hai et al., Nature 458, 489 (2009). p [9] Y. Yamane et al., Phys. Rev. Lett. 107, 236602 (2011). (γ). For quite some time the perspective has been that one

has to fix γ = γ0 where γ0 is the value of γ such that f (γ0) = 1. Y. Yamane, K. Sasage, T. An, K. Harii, J. Ohe, J. Ieda, S. E. This view is challenged in a recent work [A. Ghosh, A. Perez Barnes, E. Saitoh and S. Maekawa, ; Phys. Rev. Lett. 107, 241301 (2011)]. ‘Continuous Generation of Spinmotive Force in a Patterned In this work it is argued that the fundamental Planckian Ferromagnetic Film’, Phys. Rev. Lett. 107, 236602 (2011) discrete structure (controled by γ) has the effect of modi- fying the first law of black hole mechanics by introducing a quantum correction. Physically, a new work term appears Quantum Gravity in the first law containing the variation of the number of Black Hole Entropy and Isolated non trivial excitations of the area of the horizon (punctures) Horizons Thermodynamics times a chemical potential which is a function of γ. As a result, starting from Hawking temperature ћĸ/(2π) and According to loop quantum gravity space is made up of computing the entropy using the first law (now modified by Planckian scale discrete structures or atoms of geometry. quantum corrections) yields S = f (γ)A/(4ℓ2) in agreement This fundamental discreteness accounts for the propor- p with statistical mechanical expectations. There is no longer tionality of area and black hole entropy in loop quantum a tension: black hole entropy in LQG is modified by the gravity. The size of the quanta of geometry is controlled Immirzi parameter in a way that is consistent with Hawking by a dimensionless constant called the Barbero-Immirzi effect for a whole range of values of the Immirzi parameter. parameter (γ). In the case of the quantum area it controls This new work not only provides a possible resolution of the size of the minimum area eigenvalue or area gap. This a long standing difficulty in loop quantum gravity, but opens constant appears naturally in the action of general relativity a new door for a manifold of possible observational effects expressed in terms of connections and frames (the starting associated with the γ which by remaining free should now be point of LQG) and while it has no effect at the classical level interpreted as an additional fundamental constant in physics. (because it multiplies a topological term in the action) its appearance in the spectrum of geometric operators shows A. Ghosh and A. Perez that it has a central role in Planckian physics. ‘Black Hole Entropy and Isolated Horizons Thermodyna- Black hole thermodynamics and Hawking’s black hole mics’, Phys. Rev. Lett. 107, 241301 (2011) radiation provide ideal scenarios to study the physical role of the Immirzi parameter. This is due to the fact that quantum effects in black hole physics are well understood Bose-Einstein Condensate in the semiclassical regime (the boundary between general Phase Separation and Pattern Formation relativity and quantum gravity). It is clear from Hawking’s calculations that in the semiclassical regime, where quantum in a Binary Bose-Einstein Condensate gravity issues can be dealt with tools The determination of the equilibrium phase diagram of on curved spacetimes, black holes radiate with a temperature quantum systems at zero and finite temperature is a long (as seen by observers at infinity) equal to ћĸ/(2π). Hawking standing problem in physics. However, the experimental flex- goes on further and concludes (using the first law of BH ibility of ultra-cold atoms allows new scenarios for the study 2 mechanics) that black hole entropy is S = A/(4ℓp). of quantum dynamics. Huge departures from equilibrium are The above standard picture leads to a puzzling tension possible through the manipulation of atom confinement and in loop quantum gravity. On the one hand it is quite clear inter-particle interactions. Furthermore the universality of that (due to its semiclassical character) the particle creation phase transitions means that generic phenomena such as the calculation of Hawking is not affected in any way by the scaling of correlation functions are common across classes presence of a non-trivial Immirzi parameter. The Immirzi of transitions, despite wildly different microscopic details.

September 2012, Volume 1 No 2 27 RESEARCH HIGHLIGHTS

Modern holographic techniques allow us to spatially modulate the intensity of a laser pulse allowing us to spatially shape the coupling between the components and engineer the characteristics of our . In particular, we were able to “simulate” an inhomogeneous phase transition in a toroidal condensate. This permitted us to verify the complicated scaling of defects obtained for the classical harmonically trapped condensate in a simplified environ- ment. The technique can be extended to study characteristics of inhomogeneous phase transition, like the role of causality, that would otherwise be inaccessible.

[1] T. Kibble, J Phys A-Math Gen 9, 1387 (1976). [2] W. Zurek, Nature 317, 505 (1985). [3] W. H. Zurek, Physics Reports 276, 177 (1996). [4] M. Bowick, L. Chandar, E. Schiff, and A. Srivastava,Science 263, 943 (1994). [5] I. Chuang, R. Durrer, N. Turok, and B. Yurke, Science 251, 1336 (1991). [6] L. E. Sadler, J. M. Higbie, S. R. Leslie, M. Vengalattore, and D. M. Stamper-Kurn, Nature 443, 312 (2006). Three decades ago Kibble [1] and Zurek [2] approached [7] J. Sabbatini, W. Zurek, and M. Davis, Phys. Rev. Lett. 107, 230402 the problem of causality and formation of topological (2011). defects during a finite-temperature phase transition. Their J. Sabbatini, W. H. Zurek and M. J. Davis theory unified the physics of phase transitions at opposite ‘Phase Separation and Pattern Formation in a Binary Bose- length scales and opened the possibility to test cosmological Einstein Condensate’, Phys. Rev. Lett. 107, 230402 (2011) theories in condensed matter laboratories [3]. Ten years later Zurek extended his theory to quantum phase transi- tions further enlarging the pool of systems described by the Kibble-Zurek theory of formation of topological defects Condensed Matter during non-adiabatic processes. Exciton-Mott Physics in a Quasi-One- Several experiments reported the spontaneous forma- Dimensional Electron-Hole System tion of topological defects in condensed matter [4, 5] and ultra-cold gases [6] but the prediction of the theory about The concept of insulator-semimetal transition/crossover in the number of formed defects in function of the rate of the the system consisting of the same number of electrons and phase transition still awaits a conclusive confirmation. holes was first proposed by Mott more than half a century In [7] we use two-component Bose-Einstein condensates ago[1]. Due to the suppression of screening of long- range to investigate a quantum phase transition and test the predic- Coulomb interaction from high to low density, the metallic tions of the Kibble-Zurek mechanism in ultra-cold gases. electron-hole (e-h) plasma is expected to turn to the Binary mixtures of BECs are known to exhibit both miscible insulating exciton gas. Still, however, the examination of and immiscible phase similarly to chemical solutions. The his idea is far from being completed. We tackle this long- natural phase of a mixture is decided by the interaction standing problem by drawing a “global phase diagram” of the quasi-one- dimensional (q ) e-h systems under thermal strength between its constituent atoms. However in the case 1D where the two species are different hyperfine states linear equilibrium, developing a self-consistent screened ladder coupling can induce a transition to the other phase. In our approximation. Experimental realization of our theoretical work we drive a system from a miscible to an immiscible model is recently made in the photo-excited semiconductor phase by using a quench of the coupling strength and the quantum wire[2], and are the promising candidates of highly result of this transition is a pattern of domains separating efficient laser device. the two components. By counting the number of formed There are three possibilities of the Mott transition/ domains in function of the quench rate we were able to crossover; One is the crossover traditionally discussed in confirm the predictions of the KZ theory for an experimen- terms of the Mott density, above which any excitonic bound tally realisable scenario. states no longer exist. The second type is the first order phase 28 Asia Pacific Physics Newsletter RESEARCH HIGHLIGHTS

Classical nλ =0.2 the screening suppression by the exciton formation. At high e-h Plasma 1.0 0 density, the optical gain appears with the long low- energy 10 Saha Eq. Mott Density tails caused by the inter-carrier scattering. 1D

E [1] N. F. Mott, Can. J. Phys. 34, 1356 (1956). / 0.9 T Pure Mott [2] Y. Hayamizu et al., Phys. Rev. Lett. 99, 167403 (2007 B

k Transition 0.5 T. Yoshioka and K. Asano Unstable ‘Exciton-Mott Physics in a Quasi-One-Dimensional Quantum 0.1 Electron-Hole System’, Phys. Rev. Lett. 107, 256403 (2011) 10-1 Exciton Gas e-h Plasma 10-2 10-1 100

na1D Cosmic Rays Figure 1: Contour plot of ionization ratio on density-temperature plane. na and k T/E denote the density and the temperature in units of the Figure 1:1D ContourB plot1D of ionization ratio on density-temperature plane. na1DMeasurement of the Cosmic-Ray and kBohrT/E radiusdenote and the the binding density energy and the of the temperature one-dimensional in units exciton, of the Bohr respectively.B 1D Antiproton Spectrum at Solar Minimum radius and the binding energy of the one-dimensional exciton, respectively. with a Long-Duration Balloon nλ > 0.2. The second finding is on the appearance of an inhomogeneous phasePrecise measurement of the cosmic-ray antiproton (p¯) with sometransition first order accompanied phase transitions by an at lowinhomogeneous temperature. There, coexisting not only the divergenceregion, in the as compressibilityobserved in butthe thephotoexcited discontinuous bulk change Si inand the Ge. ionization spectrum is crucial to investigations of conditions in the early ratio isThe found. last one, which we call pure Mott transition, shows a universe and cosmic-ray propagation. Most cosmic-ray p¯’s Our interband optical absorption-gain spectra well explains semi-quantitativelyare produced by interactions of cosmic-ray nuclei with the the recentdiscontinuity experimental in observationsthe exciton inionization. the photo-excited To treat semiconductor these three quan- tum wires[2].possibilities At low on density, an equal both thefooting, excitonic we peak should and the deal band-edge with an thresh- interstellar gas. The energy spectrum of these “secondary” p¯’s old are almost unshifted in energy owing to the screening suppression by thepeaks near 2 GeV, decreasing sharply below and above due excitone-h formation. pair embedded At high density, in the the background optical gain of appears exciton-plasma with the long low- energymixture. tails caused For by this the inter-carrierpurpose, we scattering. develop a self-consistent to the kinematics of p¯ production and to the local interstellar (LIS) proton spectrum. The secondaryp ¯’s offer a unique [1] N.theory F. Mott, in Can. which J. Phys. the excitonic34, 1356 (1956). effects on the electron and [2] Y.hole Hayamizu self-energieset al., Phys. are Rev. considered Lett. 99, via 167403 the (2007).ladder Feynman ) diagrams. This enables us to define the ionization ratio, i.e., -1 BESS-Polar II GeV

the ratio of the quasi-free carrier density to the total one, -1

s BESS95+97 -1

and to estimate the plasma screening under the assumption sr -2 m ( that only these quasi-free carriers can contribute to the 10-2 x u l f 2

screening. The resultant screened interactions are fed back n

o 0 Sec: Mitsui et al. t o

to the evaluation of the ladder diagrams. r φ=600 MV p i

t Normalized @ 2 GeV n

Two main results are obtained from the phase diagram. A 1 1 Sec+Pri (A) 2 Sec+Pri (B) First, the classical-quantum crossover at around nλ = 0.2 0 characterizes the Mott-crossover, rather than the Mott Maki et al. -4 -3 -1 -3 A PBH (R=5.0 × 10 pc yr ) density, a conventionally used2 condition. Here, n and λ 10 B PBH (R=4.2 × 10-3 pc-3yr-1) denote the density and the thermal de-Broglie length evalu- φ=600 MV B ated with the e-h reduced mass. In fact, the ionization ratio, which obeyed the classical Saha equation at nλ < 0.2, behaves A

differently and starts to approach rapidly a full ionization 10-1 1 at nλ > 0.2. The second finding is on the appearance of an Kinetic energy (GeV) > 9σ n o i

inhomogeneous phase with some first order phase transi- 1 g e A B r Upper Limit

l

a (90% CL) c

tions at low temperature. There, not only the divergence i s y 0.5 h P -

in the compressibility but the discontinuous change in the n

o A BESS-Polar II ionization ratio is found. N B BESS95+97 0 0 0.002 0.004 0.006 Our interband optical absorption-gain spectra well Local Evaporation Rate of PBH (pc-3yr-1) explains semi-quantitatively the recent experimental observations in the photo-excited semiconductor quantumFigure Figure A: (Top) A: (Top) Possible Possible primary primaryp ¯ fluxes p¯ fluxes from from PBH PBH evaporation evaporation calculated calculated for BESS-Polar II (A)for and BESS-Polar BESS95+97 II (A) (B) and byfitting BESS95+97 differences (B) ofby thefitting measured differences spectra of from the the Mitsui wires[2]. At low density, both the excitonic peak and thesecondary p ¯ spectrum. (Bottom) PBH evaporation rate ( ) distributions. Values of < 0 are measured spectra from the Mitsui secondary p¯ spectrum.R (Bottom) PBH R band-edge threshold are almost unshifted in energy owing tonon-physical. evaporation rate (R) distributions. Values of R < 0 are non-physical.

September 2012, Volume 1 No 2 29

2 RESEARCH HIGHLIGHTS probe of cosmic-ray propagation and solar modulation. Ferromagnetic Insulator Cosmologically “primary” sources have also been suggested, Ferromagnetic Metal-Insulator including the annihilation of dark-matter particles and the Transition-Peierls Mechanism for evaporation of primordial black holes (PBH) by Hawking radiation Spinless Fermions

BESS95+97 confirmed that the p¯ spectrum peaks around The chromium hollandite K2Cr8O16 is a ferromagnetic 2 GeV as shown in Fig. A, and measurements by BESS and metal with a Curie temperature of 180 K. Surprisingly, this other experiments have shown that p¯’s are predominantly ferromagnetic metal undergoes a metal-insulator transition secondary. However, the low-energy p¯ spectrum measured at 95 K, remaining ferromagnetic in the insulator phase by BESS95+97 at the previous solar minimum was slightly (Fig. 1) [1]. This is the first observation of ferromagnetic flatter than predicted by secondary models. Although this metal (FM) to ferromagnetic insulator (FI) transition. In a suggested the possible presence of primary p¯’s, the large strongly-correlated electron system, such as the hollandite- statistical error of the BESS95+97 data did not allow a type oxides, ferromagnetism and metallic nature are closely firm conclusion. BESS-Polar was developed to evaluate the related with each other. Furthermore, ferromagnetic possibility of excess low-energy p¯ flux, with unprecedented insulators are extremely rare in nature. Elucidation of the precision, using long-duration solar-minimum flights over underlying mechanism, thus, has been much anticipated. Antarctica. The energy spectrum of cosmic-ray antiprotons (p¯’s) from 0.17 to 3.5 GeV has been measured using 7886 p¯’s detected by BESS-Polar II during a long-duration flight over Antarctica near solar minimum in December 2007 and January 2008. In Fig. 2 of the paper, we show the BESS-Polar II p¯ spectrum with BESS95+97 and PAMELA measurements and several calculated secondary p¯ spectra. The PAMELA spectrum generally agrees with BESS-Polar II in shape, but differs in absolute flux. The weighted mean difference, with combined uncertainties, is 14 ± 5%, calculated near 2 GeV to reduce modulation effects. Both measured spectra are consistent with solar-minimum secondary calculations. Neither exhibits the flattening at low energies found by BESS95+97, although the differences are statistically small. Cosmologically primary p¯’s have been investigated and Fig. 1. Temperature dependences of magnetic susceptibility (c) and resistivity (ρ) of K2Cr8O16. the likelihood of primary p¯’s from PBH evaporation can be quantified by a model-dependent evaporation rate (R) deter- The synchrotron x-ray diffraction for a single crystal mined by fitting a PBH model spectrum to the difference has revealed the structural change from a tetragonal I4/m of a secondary calculation from the measured flux. Using structure to a monoclinic P1121/a structure across the the Mitsui et al. secondary model and the Maki et al. PBH metal-insulator transition at 95 K [2,3]. The structure consists model with force- field modulation gives R = 5.0+4.1 × 10−4 pc−3 of the Cr O -framework and K-ions. The framework is yr−1 ,as shown in Fig. A (Fig. 4 in the paper). This excludes 8 16 constructed from the double-chains (zigzag-chains) formed by more than 9 sigma the slight possibility of primary p¯’s by edge-shared CrO octahedra. The double-chains are +1.8 −3 −3 −1 6 suggested by R = 4.2−1.9 × 10 pc yr from BESS95+97 interconnected each other through common corners of CrO data with the same models and modulation. BESS-Polar II 6 octahedra to form the Cr O -framework with tunnels occu- data show no evidence of primary p¯’s from evaporation of 8 16 pied by K+ ions. Hence, the hollandite structure has both primordial black holes. large tunnels surrounded by four double-chains and small K. Sakai et al. tunnels formed by four chains (four-chain columns). In the ‘Measurement of the Cosmic-Ray Antiproton Spectrum at tetragonal structure of the FM phase, the crystallographycally Solar Minimum with a Long-Duration Balloon Flight over independent Cr site is unique and Cr ions have an averaged Antarctica’, Phys. Rev. Lett. 108, 051102 (2012) valence of +3.75 (Cr3+/Cr4+=1/3). In the monoclinic

30 Asia Pacific Physics Newsletter RESEARCH HIGHLIGHTS

[1] K. Hasegawa, M. Isobe, T. Yamauchi, H. Ueda, J. Yamaura, H. Gotou, T. Yagi, H. Sato, and Y. Ueda, Phys. Rev. Lett. 103, 146403 (2009). [2] T. Toriyama, A. Nakao, Y. Yamaki, H. Nakao, Y. Murakami, K. Hasegawa, M. Isobe, Y. Ueda, A.V. Ushakov, D. I. Khomskii, S.V. Streltsov, T. Konishi, and Y. Ohta, Phys. Rev. Lett. 107, 266402 (2011). [3] A. Nakao, Y. Yamaki, H. Nakao, Y. Murakami, K. Hasegawa, M. Isobe, and Y. Ueda, to be published in J. Phys. Soc. Jpn. T. Toriyama, A. Nakao, Y. Yamaki, H. Nakao, Y. Murakami, K. Hasegawa, M. Isobe, Y. Ueda, A. V. Ushakov, D. I. Khomskii, S. V. Streltsov, T. Konishi and Y. Ohta ‘Peierls Mechanism of the Metal-Insulator Transition in

Ferromagnetic Hollandite K2Cr8O16’, Phys. Rev. Lett. 107, 266402 (2011) Fig. 2. Schematic illustrations of the four-chain columns for (a) the FM phase and (b) the FI phase. In the FI phase, the four-chain columns have the Cr-O (Cr-Cr) bond alternations, indicating the lattice-dimerization with the formation of Cr-tetramers. There are two types (U- and D-types) of the four-chain columns with the lattice-dimerization.

structure of the FI phase, four Cr sites (Cr1 - Cr4) become crystallographically inequivalent. However, the average values of the Cr-O bond lengths for four Cr sites are almost the same, which indicates no charge separation/order in the FI phase. Furthermore, the characteristic displacements of the Cr and O sites, resulting in Cr-O bond alternations, are observed in the four-chain columns, which indicate a dimerization of the lattice (Fig. 2). The electronic structure calculations confirmed the ferro- magnetic ground states both in the metallic and insulating phases and they also confirmed that 2K Cr8O16 is a quasi-1D electronic system characterized by the four-chain columns rather than the double-chains [2]. The lattice-dimerization observed in the four-chain columns well agrees with a Peierls transition as a nature of metal-insulator transition. Namely, the Peierls instability in the quasi-1D four-chain columns leads to Peierls transition, accompanied by the lattice-dimerization in the four-chain columns, and one extra electron is weakly localized in four Cr ions, forming Cr-tetramer. In the normal Peierls mechanism, a crystal lattice is distorted and a bond alternation is induced, while spin-up and spin-down electrons make a pair to form a singlet state. In the present case, however, it is a ferromagnetic state in which all electron spins align (full polarization) undergoes the Peierls transition, while maintaining spin polarization, indicating that it is a special case of the Peierls transition where the spin freedom of electrons plays no role. This finding is expected to lead to the development of materials with novel physical properties in which magnetism and conductivity are intricately intertwined with each other.

September 2012, Volume 1 No 2 31 ARTICLES Time-Shift in the OPERA Setup: Proof against Superluminal Neutrinos without the need of knowing the CERN–LNGS distance and Reminiscences on the Origin of the Gran Sasso Lab, of the Third Neutrino and of the “Teramo Anomaly”*

Antonino Zichichi INFN and University of Bologna, Via Zamboni, 33-40126 Bologna, Italy CERN, CH-1211, Geneva 23, Switzerland

The LVD time stability allows one to establish a time-shift in the ago, the existence of an anomaly in the mountain structure, OPERA experiment, thus providing the first proof against superlu- which exhibits a low m.w.e. (meter, water, equivalent) thick- minal neutrinos, using the horizontal muons of the “Teramo Anomaly.” ness for horizontal directions. This proof is particularly interesting because it does not need the The “abundant” high-energy horizontal muons (nearly knowledge of the distance between the location at which the neutrinos 100 per year) going through LVD and OPERA exist because are produced (CERN) and the location they are detected (LNGS). Since of this anomaly in the mountain orography. It is these muons the superluminal neutrinos generated in the physics community a which allow us to have a time-correlation, between different vivid interest in good and bad behavior in physics research, the author setups. thought it was appropriate to recall the origin of the Gran Sasso Lab, In this paper after the “Teramo Anomaly,” discussed in of the third neutrino, of the horizontal muons due to the “Teramo Sec. 2, I will recall the origin of the third neutrino (Sec. 3) Anomaly” and of the oscillation between leptonic flavors, when the since the purpose of OPERA was (and is) to measure the CERN–Gran Sasso neutrino beam was included in the project for the oscillations between the neutrinos of the second and third most powerful underground laboratory in the world. families, the last one being now called ντ , but originally

designated as νHL where the subscript HL stands for Heavy Keywords : Neutrino; Gran Sasso Lab; OPERA; Teramo Anomaly. . In Secs. 4 and 5 few words will be devoted to the LVD and OPERA setups, respectively. The crucial measurement 1. Introduction of the time-shift between LVD and OPERA will be treated in Sec. 6. I will give my conclusions in Sec. 7 and followed The purpose of this paper is to report the measurement of a by acknowledgments at the end. time-shift in the OPERA setup in a totally independent way from time-of-flight (TOF) measurements of CNGS neutrino events and without the need of knowing the distance 2. The Discovery of the “Teramo Anomaly” (An between the two laboratories, CERN and LNGS, at which the Example of How to Avoid Big Mistakes) and the neutrinos are produced and detected, respectively. This can Problem of Experimental versus Theoretical Papers be done thanks to the existence of the “Teramo Anomaly.” How did we discover this “anomaly” is an example of how The LVD and OPERA experiments are both installed in the to avoid big-mistakes.1,2 same laboratory: LNGS. Indeed, the OPERA–LVD direction The problem was to search for Galactic Center Super- lies along the so-called “Teramo Anomaly,” a region in the novae (SN). Why? Because from Keplero–Galilei last Gran Sasso massif where LVD has established, many years Supernova (SN) there are four centuries. The rate of SN per Galaxy per century is 3. The number of missing SN is 12. * Based on an invited talk at the Gran Sasso mini-Workshop on LNGS How can this be explained? Answer: the light emitted results on the neutrino velocity topic, Gran Sasso, 28 March 2012. 32 Asia Pacific Physics Newsletter ARTICLES by SN is what we observe. But the center of our Galaxy is and nothing happens. In it is forbidden with enormous light emission. Conclusion: the center of our to make mistakes. Being a member of the Blackett School, Galaxy has to be observed not thanks to the light emitted by instead of being excited by a fast conclusion, we decided a SN but by neutrino-emission-effects. to go on in our search. This is how we discovered that the Notice that all supernovae known so far have been center of our Galaxy had nothing to do with the intense flux detected thanks to light but they are all in a galactic-space of muons (the “Teramo Anomaly”). This flux was due to an where the number of Stars is ~_ 10% of the total number. unexpected anomaly in the mountain density. This “beam” Therefore the number of missing SN in four centuries is of muons could be of great value for the Gran Sasso experi- not 12 but ~_ 1.2. The number of missing SN would be 12 if ments, as proved by our meeting here. the telescopes for neutrinos from SN were active during the A sketch of the LNGS map with the position of LVD and past four centuries. OPERA experiments is shown in Fig. 1. But it is only since 1992 that we have the LVD telescope Indeed, the OPERA–LVD direction lies along the being active for the observation of SN neutrino. Since the anomaly in the mountain profile observed in 19971,2 when expected number is one supernova every 30 years, the searching for neutrino events from the center of the Galaxy. number of years of active LVD being only 20, the effective The anomaly is due to the nonuniform rock structure number of missing SN when the observation includes the in the horizontal direction toward the city of Teramo, thus neutrino is ~_ 0.7. called “Teramo Anomaly.” The number of SN expected to be observed via light This is due to a large decrease in m.w.e. of the mountain mission during four centuries (1.2) and the number of SN rock structure, as indicated in Fig. 2 by the red circle. expected to be observed by ν telescopes during the past 20 years (0.7) are in purely accidental agreement. If we are lucky we should observe with LVD a SN in the next years to come. This is why when we started with our LVD telescope we focused our attention to look toward the center of our Galaxy: not only for SN neutrinos but also as a source of unexpected events giving rise to any sort of anomaly in our detectors. Looking at the center of our Galaxy we discovered the “Teramo Anomaly,” i.e. high-energy muon flux _ ~ 100 per year. This anomaly could have produced a paper where the effect was attributed to what happens in the center of our Galaxy. But we are not a theorist whose model can be wrong

Fig. 2. Map of the slant depth of the Gran Sasso mountain (in m.w.e.) as a function of the arrival direction: θ and ϕ are respectively the zenith and azimuth angle. The red circle indicates the direction of the “Teramo valley,” where the mountain profile exhibits an “anomaly” in the m.w.e. for horizontal directions.

Let me say a few words to explain my previous statement of being member of the Blackett group. When I started my research activity I had the privilege of being a pupil of Professor Patrick M. S. Blackett whose famous statement was: We experimentalists are not like theorists : the originality of an idea is not for being printed in a paper, but for being shown in the implementation of an original experiment (London 1962). This statement (Fig. 3) is at the entrance of the Blackett Fig. 1. (Color online) Sketch of the LNGS map with the position of the LVD and OPERA experiments. Institute of the EM- FCSC in Erice.

September 2012, Volume 1 No 2 33 ARTICLES

3. The Origin of the Third Neutrino and Some Reminiscences of How the Gran Sasso Lab Could Become Real What is now called τ-lepton represents the origin of the third family of fundamental fermions. The search for a lepton heavier than the muon started at CERN with the PAPLEP (Proton Antiproton Annihilation into Lepton Pairs) (pp¯) experiment in the early sixties, before the discovery in 1964 of PC-violation by J. Christen- son, J. W. Cronin, Val L. Fitch, and R. Turlay4 and the proposal in 1973 by M. Kobayashi and T. Maskawa5 for the existence of a third family Fig. 3. of fundamental fermions. Since the scientific motivation for OPERA is to detect the And here comes another crucial point which distin- oscillation between the second and the third neutrinos, it is guishes experimental physics papers from theoretical physics appropriate to establish the origin of this physics. papers. Figure 4 shows the cover page of the volume due to Mme Many years ago there was a seminar at CERN devoted to C. S. Wu to whom I want to renew my gratitude. this problem.3 During the discussion I quoted the viewpoint Figure 5 shows the experimental setup constructed in of Feynman about punishing the authors of models which the early sixties at CERN- for the search of the third lepton had no relation with physics reality and Martinus Veltman called by us at that time as HL. expressed his support. As every body knows this viewpoint is the basis of the famous statement by : I don’t mind that you think slowly but I do mind that you are publishing faster than you think. Unfortunately the status of experimental paper versus theoretical paper is as given below:

(a) Theorist => if the model is not corroborated by an experimental result: nothing happens. The theoretical physicist does not lose his reputation. (b) Experimentalist => if the experimental result is not corroborated by other experimental results, the experi- mental physicist loses his reputation. Fig. 4.

This is the reason why we, experimental physicists, must be extremely careful in letting people knowing even confidentially, if we find what could be a very interesting result. In fact the more interesting the result is, the more careful we must be. Also because you can never be sure that, after talking to a colleague, he is going to keep the secret for himself. The lesson from the past is very instructive. Let me quote the case when proton was proposed to be the antielectron by Dirac; Kapitza was responsible for this, as I report in the Erice folder (distributed to all participants every year since 1963). I want to skip this amusing example since it is known to all physicists coming to Erice, while very few people know the origin of the OPERA main physics task: to study the oscillations between the two neutrinos νµ and ντ. Fig. 5. The PAPLEP experimental setup at CERN.

34 Asia Pacific Physics Newsletter ARTICLES

This setup is the first example of the gigantic setups now correctly represented is in the bottom-left of Fig. 6. needed to do physics as it is the OPERA detector. From In Fig. 6 the physics roots are dated 1960. These roots PAPLEP to OPERA there are four decades; nevertheless the gave rise to the Gran Sasso Project (1979) where the study search for third leptonic family started at CERN four decades of oscillations between νµ and νHL was indeed included, as ago using as production process (pp¯) annihilation. testified by Pontecorvo (see later).

Fig. 7.

Fig. 6. If the third lepton would have been discovered at CERN we would not have used the symbol τ for the very simple No one knew the existence of the very large Electromag- reason that the τ and θ were two mesons decaying into three netic Form Factor (EMFF) of the nucleon in the timelike and two respectively and you cannot use the same region when PAPLEP was proposed. This large EMFF gave symbol to indicate another particle. Furthermore, these two as a result a depression factor more than 500 in the (pp¯) mesons, τ and θ, gave rise to the famous “(τ − θ) puzzle” annihi- lation cross-section for the productions of pairs of discovered by Richard Dalitz.6–8 , a — the third lepton (HL) (HL). This is why the search moved to All this was neglected by those who, instead of using for + − ± Frascati where the production process was (e e ). the third lepton the (HL ) and for the neutrinos (νHL, ν¯HL)

The search for the existence of third lepton at CERN introduced the notation τ and ντ: i.e. was not a sporadic event. The possible existence of a lepton heavier than the muon had its roots in the research activity HL => τ , νHL => ντ . of this great new laboratory in Europe, where attention was given to the validity of QED when particles 200 times heavier The (τ − θ) puzzle was not a trivial detail; it produced the than an electron were involved. breaking of Parity and of Charge Conjugation Invariance in This is why the high precision determination of the muon 1954 thanks to T. D. Lee and C. N. Yang.10–13 anomalous magnetic moment of (g − 2)µ was performed. Dalitz, the author of the (τ − θ) puzzle, regretted very And the problem of establishing the universality of the weak much that the existence of the large timelike (EMFF) of the forces was studied, with the first high precision measurement nucleon did not allow the discovery of the third lepton at of the weak coupling, through the muon decay lifetime: τµ . CERN in the early sixties. For the very simple reason that, in The reason for the abundance of muons was the incredible this case as often pointed out by Dalitz, the notation would th mass difference between the π-meson and its decay partner, not be τ and ντ but HL and νHL . This is why the 44 course the µ-lepton. The problem was that if this incredible coinci- of the Subnuclear Physics School in Erice was dedicated to dence did not repeat in the GeV range. In this case a third Richard Dalitz (Fig. 7). lepton much heavier than the muon, HL, could be there but Talking about new ideas, since there are many young very rare since the sequence π → µ was unlikely to be there physicists in the audience, it is appropriate to recall what for the pair of heavy meson → heavy lepton. A schematic view of the present status of the electroweak a For a detailed record of the events which led to the (θ − τ ) puzzle forces where the origin of the third family of is see Ref. 9.

September 2012, Volume 1 No 2 35 ARTICLES

Isidor I. Rabi, the founder of the formidable School of Physics in USA, the Physics Department of Columbia University (NY) said:

Fig. 9.

Fig. 10. Reproduction of page 13 of the original project.14 Fig. 8. (Fig. 10) presented by me at the Commission on Public Physics needs new ideas. But to have a new idea is a very Works of the Italian Senate. difficult task : it does not mean to write a few lines in a paper. There are two figures (Figs. 11 and 12) which I presented If you want to be the father of a new idea, you should fully at the Commission in 1979, afterhaving discussed with the devote your intellectual energy to understand all details and President of the Italian Republic, Sandro Pertini, the new to work out the best way in order to put the new idea under projects for the future activities of the INFN. experimental test. This can take years of work. You should Figures 11 and 12 produced a great interest in our Presi- not give up. If you believe that your new idea is a good one, dent, who became a strong supporter of the INFN five-year you should work hard and never be afraid to reach the point plan where the proposal was to have an increase of the budget where a new-comer can, with little effort, find the result you by an order of magnitude: from 20 billion lira to 200 billion have been working, for so many years, to get. The new-comer lira. My friends were saying Nino is dreaming; the nonfriends can never take away from you the privilege of having been the were using less gentle expressions. first to open a new field with your intelligence, imagination and hard work. Do not be afraid to encourage others to pursue your dream. If it becomes real, the community will never forget that you have been the first to open the field . (1972).

This is reproduced in a bronze sculpture placed in the I. I. Rabi Institute of the EMFCSC in Erice (Fig. 8). The ceremony was chaired by Tsung Dao Lee (Fig. 9). As you all know the physics of OPERA is focused to the Fig. 11. Handwritten notes from the presentation by A. Zichichi to the Commission on Public Works of the Senate in a Session convened on study of neutrino oscillations which, as mentioned before, short notice by the President of the Senate to discuss the proposal for was indeed in the scientific aims of the Gran Sasso Project Gran Sasso Project (1979).

36 Asia Pacific Physics Newsletter ARTICLES

stop the joint venture between Italy and France to realize an underground laboratory in the Fréjus tunnel. After this unprecedented attack against a very important initiative in Italy, the other CERN Director General, John Adams, called me into his office, to tell him not to worry. This ended all attacks from CERN against the project. The arrival of Pontecorvo in Italy gave rise to a new set of actions. During the visit and the various lectures by Pontecorvo, a journalist asked: “Professor Pontecorvo, what Fig. 12. do you think of the Gran Sasso Project proposed by Professor Zichichi? Many physicists consider it a useless Napoleonic I want to recall that, for the first time in the history of venture with weak scientific content.” After a few seconds INFN, the presentation was at the special Hall of the Italian of thinking, in the usual Pontecorvo style of soft and slow Parliament and in the first rank there was the President of answering, he said: “I regret not to be young enough to the Italian Republic, Sandro Pertini with many members of participate in this formidable project. The scientific content the Government. of the project appears to me extremely interesting.” Nevertheless many physicists, who Fermi would have This declaration by Pontecorvo came as a surprise, since classified of second and third-rank, were continuing their we were on opposite political sides and every journalist was campaign against the Gran Sasso Project. expecting a strong negative statement from him on the Gran Fortunately, (Fig. 13) was suddenly Sasso Project. But physics prevailed. And this put an end to allowed to visit Italy. The Berlin Wall was up and this became all — open as well as underground — lobbying against the a great occasion for the media. It was the time when the Gran Sasso Project. Gran Sasso Project was being discussed in the scientific Pontecorvo never lost any occasion to emphasize the environment. value of studying the oscillations between neutrino flavors. In The so-called “Rome School” tried to bring to a halt the fact in his original paper he was suggesting the study of (ν ν¯ ) “Gran Sasso Project” with arguments similar to those used at oscillations. The flavors oscillations came later, as reported Frascati with ADONE to boycott the energy increase of the in a note by Gillo Pontecorvo (Fig. 14). (e+ e−) collider (“Zichichi is searching for butterflies”), when I was searching for the third lepton after PAPLEP using the (e+ e−) annihilation many years before M. Perl.

Fig. 13. The author and Bruno Pontecorvo, Rome, September 1978.

Underground lobbying by the “Rome School” had produced effects. For instance the CERN Director General (DG) Leon Van Hove, during a CERN council meeting declared that Zichichi’s Gran Sasso Project was invented to Fig. 14.

September 2012, Volume 1 No 2 37 ARTICLES

Fig. 16. (Color online).

Fig. 15. Reproduction of page 111 of Ref. 15; Proceedings in honour of M. Con- versi, a strong supporter of the Gran Sasso Project.

Let me close this brief recollection of the origin of the Fig. 17. This picture shows the pre-Big Bang zone, which is at the center of theoretical attention today. LNGS showing the basic characteristics of the Lab (Fig. 15), the cover page (Fig. 16) of a volume edited by Sandro Bettini, on the occasion of the XX Anniversary of the Gran Sasso Lab and a synthesis of the evolution of the three gauge couplings (Fig. 17). This evolution was studied in order to illustrate the complementarity of the Gran Sasso Project and the other projects (LEP, LHC and ELN) where high-energy colliders were involved. The complementarity of all projects proposed in the five-year plan of INFN (where theincrease by an order of magnitude for the financial support was requested) had to be proved with strong physics arguments in order to convince first rank fellows. Fig. 18. This is because, during the difficult times of the Gran Sasso Projects there were second and third rank people called Let me recall statement where the meaning physicist doing underground lobbying and stating that this of the second- and third-rank fellows is given: There are project was against the other Italian engagements in Europe several categories of scientists in the world ; those of second or which I had included in the five-year plan of INFN. third rank do their best but never get very far. Then there is the In fact in addition to the Gran Sasso Project, I presented first rank, those who make important discoveries, fundamental two other important engagements for our country, LEP in to scientific progress. But then there are the geniuses, like Galilei Geneva and HERA in Hamburg. and Newton. Majorana was one of these (Rome 1938).

38 Asia Pacific Physics Newsletter ARTICLES

In order to convince first rank fellows you need strong Since these are times when the physics community is arguments,16, b such as the Renormalization Group Equations, interested in good and bad behavior in physics research I originated in 1951 by my friend Andr´e Petermann who was thought it was appropriate to recall that, when the Gran Sasso the pupil of Stueckelberg.17–23 , c Project was elaborated, the CERN–Gran Sasso neutrino The mathematical formalism which has been used to beam was proposed as a good experiment to be done in order obtain the results shown in Fig. 17 is a system of three to study the oscillations between the muon neutrinos νµ and nonlinear differential equations coupled via the gauge the νHL. Let us not loose the memory, as Enrico Fermi wanted. couplings I will now say a few words on the LVD and OPERA detectors and then discuss the results obtained by the

αi , αj (with i = 1, 2, 3; and j = 1, 2, 3 but i ≠ j) , collaboration between the two groups, LVD and OPERA, in order to establish if a time-shift occurred during the calendar as shown in Fig. 18. years (1997–2012). During more than ten years (from 1979 to 1991), no one had realized that the energy threshold for the existence of 4. The LVD Detector the “Superworld” was strongly dependent on the “running” 43 of the masses.24 The LVD (Large Volume Detector) (Fig. 19) is located This is now called: the EGM effect (from the initials in Hall A of the INFN underground Gran Sasso National of Evolution of Gaugino Masses). To compute the energy Laboratory at an average depth of 3600 m.w.e. The LVD main threshold using only the “running” of the gauge couplings purpose of LVD is to detect and study neutrino bursts from galactic gravitational stellar collapses. (α1, α2, α3) corresponds to neglecting nearly three orders of magnitude in the energy threshold for the discovery of the The experiment started taking data in June 1992 and has first particle (the lightest) of the Superworld.25–42 continued without interruptions until now. The detector, The reason why I have devoted some attention to all these schematically shown in Fig. 20, consists of an array of 3 past details is in another Fermi statements: Neither science 840 liquid scintillator counters, 1.5 m each, arranged in a nor civilization could exist without memory. compact and modular geometry: 8 counters are assembled If we are here today, if the Gran Sasso Lab exist, if LVD in a module called “portatank”; 35 portatanks (5 columns × and OPERA collaborate, if all this can happen, this is because 7 levels) form a “tower”; the whole detector consists of three all the difficulties mentioned before have been passed. identical towers that have independent power supply, trigger The difficulty we are facing today is just an example of the and data acquisition systems. problems which need to be overcome having as primary purpose to do good physics. Good physics was (and is) the reason why OPERA has been built: i.e. to study the oscillation between the second and the third family neutrinos. b The statement on page 2 of this paper, Unification of all forces needs first a supersymmetry. This can be broken later, thus generating the sequence of the various forces of nature as we observe them , was based on a work by A. Petermann and A. Zichichi in which the renormalization group running of the couplings using supersym- metry was studied with the result that the convergence of the three couplings improved. This work was not published, but perhaps known to a few. The statement quoted is the first instance in which it was pointed out that supersymmetry might play an important role in the convergence of the gauge couplings. In fact, the convergence of three −1 –1 –1 straight lines (α1 α2 α3 ) with a change in slope is guaranteed by the Euclidean geometry, as long as the point where the slope changes is tuned appropriately. What is nontrivial about the convergence of the couplings is that, with the initial conditions given by the LEP results,

the change in the slope at MSUSY ~ 1 TeV is not correct, as claimed by some authors not aware in 1991 of what was known in 1979 to A. Petermann and A. Zichichi. Fig. 19. Photograph of the LVD detector in Hall A of the underground c For an excellent description of the subject see Ref. 21. Gran Sasso Labs.

September 2012, Volume 1 No 2 39 ARTICLES

The modularity of the apparatus allows for calibration, maintenance and repair interventions without major nega- tive interference with data taking and detector sensitivity. Figure 21 shows the duty cycle and the trigger active mass of LVD from June 1992 to March 2011. From 2001 the experiment has been in very stable conditions with duty cycle > 99% and slightly increasing active mass. The minimum trigger mass of 300 ton, corresponding to less than one “tower”, at which LVD can monitor the whole Galaxy for gravitational core collapses is also shown (blue).

5. The OPERA Detector OPERA is a hybrid experiment with electronic detectors and nuclear emulsions located in Hall C of the underground Fig. 20. Schematic view of the LVD apparatus. Gran Sasso Laboratory.44 The main physics goal of the experi- ment is to observe neutrino flavor oscillations through the

appearance of ντ via the production of a τ lepton in the νµ CNGS beam. The detector design was optimized to identify the τ lepton via the topological observation of its decay: this requires a target mass of more than a kiloton to maximize the neutrino interaction probability and a micrometric resolution to detect the τ decay.

Fig. 21. (Color online) LVD duty cycle and active mass in the period June 1992–March 2011.

The external dimensions of the active volume are 13 × 23 × 10 m3. The liquid scintillator (density ρ = 0.8 g/cm3) is

Cn H2n with = 9.6 doped with 1 g/l of PPO (scintillation activator) and 0.03 g/l of POPOP (wavelength shifter). The total active scintillator mass is M = 1000 ton. Each LVD counter is viewed from the top by three 15 cm diameter photomultipliers (FEU49 or FEU125). The main reaction that is detected by LVD is the inverse

+ (ν¯ e p, ne ) , which gives two signals: a prompt one due to the e+ followed by the signal from the neutron capture reaction (np, dγ) with mean capture time of about

Fig. 22. Distribution of the δt = tLVD − tOPERA for each period of time. In the vertical axis the number of events; in the horizontal axis t in ns. 185 µs and Eγ = 2.2 MeV. δ 40 Asia Pacific Physics Newsletter ARTICLES

6. The Time Difference Between LVD and OPERA Let us now group the results in two classes: • Class A: Between August 2007 to August 2008 and from The time difference between LVD and OPERA is given by January to March 2012. • Class B: From August 2008 to December 2011. δt = tLVD − tOPERA . The two distributions for Class A and Class B are reported In order to study the stability of the time difference δt in Fig. 24. versus calendar time, the data have been subdivided in We obtain for Class A, different periods of the various solar years. The year 2008 has been divided in three samples: before May, May–August, and δt = (595 ± 8) ns , after August. For each period we look at the δt distribution, compute the mean and the RMS. while for Class B, The results are shown in Figs. 22 and 23 and are summarized in Table 1. The total number of events, 306, is δt = (668 ± 4) ns. distributed into eight samples, each one covering a given calendar time period. In Fig. 25 we report the average value

<δt>

for the two classes.

Fig. 23. Distribution of the δt = tLVD − tOPERA for corrected events. All the events of each year are grouped in one single point with the exception of year 2008 which is subdivided in three periods: before May, May–August, after August.

Table 1. Summary of the δt distribution in the various calendar time periods.

Total Number of Events = 306 Class Year Since To No. of events (δt) (ns) A 2007 Aug Dec 18 577 ± 10 A 2008-1 Jan Apr 14 584 ± 20 A 2008-2 May Aug 23 628 ± 11 A 2012 Jan Mar 9 567 ± 16 B 2008-3 Sep Dec 25 669 ± 11 B 2009 Jun Nov 47 669 ± 9 B 2010 Jan Dec 63 670 ± 8 B 2011 Jan Dec 107 667 ± 5 Fig. 24. Distribution of δt = tLVD − tOPERA for events of Class A and Class B.

September 2012, Volume 1 No 2 41 ARTICLES

so-called “Teramo Anomaly,” where the mountain profile exhibits an anomaly in the m.w.e. depth in the horizontal direction. Visual inspection using the event displays of LVD and OPERA detectors confirms this anomaly discovered by LVD in 1997.1,2 The calendar time evolution of the time-difference δt for various periods of data-taking is shown in Fig. 23. We see an evolution of the average value in each period, ranging from

~580 ns in 2007 up to ~ 670 ns

Fig. 25. Average value of δt computed in each class of events. Class A are from May 2008 to the end of 2011; then for the nine events in calendar time from August 2007 to August 2008 and from January 2012 to March 2012; Class B are from August 2008 to December 2011. events collected so far in 2012 it decreases again to

The resulting time difference between the average values ~ 570 ns . in the two classes is The observed variations are larger than the statistical uncertainty estimated for each period. ∆AB = <δtA> − <δtB> = (−73 ± 9) ns , Grouping the time periods in two classes, as labeled in far from zero at 8-sigma level. Table 1, we obtain for Class A an average value of We also note that now, after doing all the needed correc- tions, the two Gaussian distributions have a width compatible ∆t(A) = (595 ± 8) ns , with the ~ 50 ns time accuracy claimed by the experiments. The stability in time of LVD shows that the OPERA and for Class B detector has a negative time-shift in the calendar period from August 2008 to December 2011 of the order of ∆t(B) = (668 ± 4) ns .

∆AB = (−73 ± 9) ns The time stability of LVD compared with that of the OPERA detector gives a time difference between the two compared with the calendar time from August 2007 to classes August 2008 and from January to March 2012 taken together. ∆t(A − B) = (−73 ± 9) ns .

This corresponds to a negative time shift for OPERA in 7. Summary and Conclusions the calendar period from August 2008 to December 2011 of Data from horizontal muons traversing the LVD and OPERA the same order of the excess leading to a neutrino velocity detectors cover a calendar time period from mid 2007 until higher than the speed of light as reported by OPERA.45 2012, for a total life time of about 1200 days. Recent checks of the OPERA experimental apparatus In a time-window of 1 µs, and excluding events in time showed evidence for equipment malfunctionings.46 with the CNGS beam spill, we found 306 events due to The first one is related to the oscillator used to produce horizontal muons from the “Teramo Anomaly.” the event time-stamps, while the second one is linked to the

This sample has a time-difference (tLVD − tOPERA ) distribu- connection of the optical fiber bringing the GPS signal to tion peaked at 616 ns with an RMS of 74 ns. the OPERA master clock. The central value of the distribution has the following This allows us to conclude that the quantitative effect of interpretation: the coincident events detected up to now this malfunctioning is the negative time-shift, ∆t(A − B), are not multiple muons (one per each detector), but single mentioned above. muon events entering horizontally from the OPERA side This explains the previous OPERA finding45 on the and going through the LVD detector after 616 ns of flight. neutrino TOF shorter by 60 ns over the speed of light. Indeed, the OPERA–LVD direction lies along the The result of this joint analysis is the first quantitative

42 Asia Pacific Physics Newsletter ARTICLES measurement of the relative time stability between the two References detectors and provides a check that is totally independent 1. LVD Internal Note, 1997. from the TOF measurements of CNGS neutrino events and 2. A. Zichichi (for LVD Group), Unexpected results from from the effect presented in Ref. 46, pointing to the exist- the Gran Sasso Lab, EPS Conf., September 1997, Erice, ence of a possible systematic effect in the OPERA neutrino Highlights of Subnuclear Physics [presented also at the velocity analysis. Conference Ten Years LVD Celebration LNGS-2002]. If new experiments will be needed for the study of 3. B. French, F. James, L. Kowarski, M. Veltman and A. neutrino velocities they must be able to detect effects of an Zichichi, Comput. Phys. Commun. 3(Suppl. 1), 157 (1972). order of magnitude smaller than the value of the OPERA 4. J. Christenson, J. W. Cronin, V. L. Fitch and R. Turlay, systematic effect. This could be done47 by upgrading LVD Phys. Rev. Lett. 13, 138 (1964). with high TOF resolution.48 5. M. Kobayashi and T. Maskawa, Prog. Theor. Phys. 49, 652 (1973). 6. R. H. Dalitz, Phil. Mag. 44, 1068 (1953). Acknowledgments 7. R. H. Dalitz, Proc. Phys. Soc. A 69, 527 (1956). I would like to express my thanks to the CERN Research 8. R. H. Dalitz, Proc. Sixth Annual Rochester Conference on Director, Sergio Bertolucci, and to the INFN President, High Energy (Interscience Publishers, Inc., Fernando Ferroni, for their wilful dedication to the solution New York, 1956), p. 19. to the problems which came up during the long period it took 9. R. H. Dalitz, decays to pions: The τ−θ problem, in to finalize the results presented in this report. These results History of Original Ideas and Basic Discoveries in Particle Physics, eds. H. B. Newman and T. Ypsilantis (Plenum required the collaboration of the members of the OPERA Press, New York and London, 1994), p. 163. and LVD groups, to whom I would also like to address my 10. T. D. Lee and C. N. Yang, Phys. Rev. 104, 254 (1956). thanks, and in particular to Antonio Ereditato, Gabriella 11. C. S. Wu, E. Ambler, R. W. Hayward and D. D. Hoppes, Sartorelli and the staff of the INFN–LNGS for excellent work. Phys. Rev. 105, 1413 (1957). 12. R. Garwin, L. Lederman and M. Weinrich, Phys. Rev. 105, 1415 (1957). Antonino Zhichichi is Emeritus 13. J. J. Friedman and V. L. Telegdi, Phys. Rev. 105, 1681 (1957). Professor of the University of 14. A. Zichichi, The Gran Sasso project, in Proc. GUD- Bologna and CERN. He was the Workshop on Physics and Astro- physics with a Multikiloton President of the Italian National Modular Underground Track Detector, Rome, Italy, 29–31 Institute for Nuclear and Subnuclear October 1981 (INFN, Frascati, 1982), p. 141. Physics Physics, the President of 15. A. Zichichi, Perspectives of underground physics: the European Physical Society. The Gran Sasso project, Invited Plenary Lecture at the Symposium on Present Trends, Concepts and Instruments of Particle Physics, in Honour of Marcello Conversi’s 70th Birthday, Rome, Italy, 3–4 November 1987, eds. G. Baroni, L. Maiani and G. Salvini, Conference Proceedings, Vol. 15 (SIF, Bologna, 1988), p. 107. 16. A. Zichichi, Rivista del Nuovo Cimento 2, 1 (1979). 17. E. C. G. Stueckelberg and A. Petermann, Helv. Phys. Acta 24, 317 (1951). 18. E. C. G. Stueckelberg and A. Petermann, Helv. Phys. Acta 26, 499 (1953). 19. M. Gell-Mann and F. E. Low, Phys. Rev. 95, 1300 (1954). 20. N. N. Bogoliubov and D. V. Shirkov, Introduction to the Teory of Quantized Fields (Interscience Publishers, New York, 1959). 21. S. Coleman, Renormalization and symmetry: A review for non-specialists, in Properties of the Fundamental Interac- tions, Erice 1971, ed. A. Zichichi (Editrice Composi- tori, Bologna, 1973), p. 605.

September 2012, Volume 1 No 2 43 ARTICLES

22. A. Petermann, Phys. Rep. 53, 157 (1979). 38. OPAL Collab. (M. Z. Akrawy et al.), Phys. Lett. B 248, 211 23. J. C. Collins, Renormalization (Cambridge University (1990). Press, 1984). 39. P.D. Acton et al., preprint CERN-PPE/91-115, 22 July 24. F. Anselmo, L. Cifarelli, A. Peterman and A. Zichichi, 1991. Nuovo Cimento A 105, 581 (1992). 40. MARK II Collab. (T. Barklow et al.), Phys. Rev. Lett. 64, 25. ALEPH Collab. (D. Decamp et al.), Phys. Lett. B 236, 86 2984 (1990). (1990). 41. M. Davier, Searches for new particles at LEP, LP-HEP 91 26. ALEPH Collab. (D. Decamp et al.), Phys. Lett. B 237, 291 Conference, Geneva, CH, preprint LAL 91-48, December (1990). 1991. 27. ALEPH Collab. (D. Decamp et al.), Phys. Lett. B 244, 541 42. F. Anselmo, L. Cifarelli, A. Peterman and A. Zichichi, (1990). Nuovo Cimento A 105, 581 (1992). 28. ALEPH Collab. (D. Decamp et al.), Phys. Lett. B 265, 475 43. LVD Collab. (M. Aglietta et al.), Nuovo Cimento A 105, (1991). 1793 (1992). 29. DELPHI Collab. (P. Abreu et al.), Phys. Lett. B 241, 449 44. OPERA Collab. (R. Acquafredda et al.), J. Instrum. 4, (1990). P04018 (2009). 30. DELPHI Collab. (P. Abreu et al.), Phys. Lett. B 245, 276 45. T. Adam et al., Measurement of the neutrino velocity (1990). with the OPERA detector in the CNGS beam, arXiv:1109.4897v2. 31. DELPHI Collab. (P. Abreu et al.), Phys. Lett. B 247, 148 (1990). 46. OPERA Internal Note 143, 2012, report to the SPSC and LNGS-SC, March 2012. 32. DELPHI Collab. (P. Abreu et al.), Phys. Lett. B 247, 157 (1990). 47. A. Zichichi (for the LVD and EEE Groups), Proposal for an MRPC system with high precision timing in the LVD 33. L3 Collab. (B. Adeva et al.), Phys. Lett. B 233, 530 (1989). structure, CERN-INFN preprint, 19 December 2011. 34. L3 Collab. (B. Adeva et al.), Phys. Lett. B 251, 311 (1990). 48. S. An, Y. K. Jo, J. S. Kim, M. M. Kim, D. Hatzifotiadou, M. 35. L3 Collab. (B. Adeva et al.), Phys. Lett. B 252, 511 (1990). C. S. Williams, A. Zichichi and R. Zuyeuski, Nucl. Instrum. 36. OPAL Collab. (M. Z. Akrawy et al.), Phys. Lett. B 240, 261 Methods Phys. Res. A 594, 39 (2008). (1990). 37. OPAL Collab. (M. Z. Akrawy et al.), Phys. Lett. B 242, 299 (1990).

World Scientific Connecting Great Minds

edited by Gordon Kane edited by Dan Green edited by Gordon L Kane by Roberto Tenchini (INFN Pisa) & Aaron Pierce (Fermi National Accelerator Laboratory) (University of Michigan) & Claudio Verzegnassi (University of Michigan) (University of Trieste) AD/PK/09/12/04/HC www.worldscientific.com

44 Asia Pacific Physics Newsletter AD_PK_09_12_04_HC.indd 1 21/9/12 4:40 PM ARTICLES The Daya Bay Experiment and the Discovery of a New Type of Neutrino Oscillation

Yifang Wang Institute of High Energy Physics, Chinese Academy of Sciences Beijing, 100049, P.R. China

e know nowadays that the matter world we live in is made of 12 elementary particles, including 6 , 3 charged leptons and 3 neutrinos. WAmong them, neutrinos are least known since they do Fig.1. Three types of neutrino oscillation not carry the electric charge and interact with others only

weakly(often referred as the nuclear weak interactions). In The unknown mixing angle 13θ is the target of the Daya the Standard Model of particle physics before 1998, neutrinos Bay experiment. This number is not only a fundamental are considered as massless for simplicity and lack of parameter of neutrino physics, its value will also determine experimental evidence. However, they are so abundant in the the future of the neutrino physics: if it is large enough, the universe that their masses, even if tiny, will have significant future experiments to measure neutrino mass hierarchy and impact to the particle physics, astrophysics and cosmology. CP phase can be planed, otherwise we have no idea how to Up to now, neutrino studies are still focusing on some of proceed.

the fundamental questions: What is the neutrino mass? Do Measure θ13 using nuclear power reactors are ideal since World Scientific they have internal structure? Is the right-handed neutrino reactors can produce enormous electron anti-neutrinos Connecting Great Minds the same as its anti-partner? Here neutrino mass is the most during the fission reaction. The survival probability of these

wanted answer due to its importance to the astrophysics neutrinos, Pee, if they oscillate, can be written as the following: and cosmology. 2 2 2 A special property, called neutrino oscillation is proposed Pee ≈ 1 − sin 2θ13sin (1.27Δm 13L/E) + Corr. Terms, by Bruno Pontecorvo in 60’s. He postulated that if neutrinos have mass, and their mass eigenstates and weak interaction where L is the distance between the neutrino source 2 eigenstates are not the same, as a consequence of Quantum and the detector, E is the neutrino energy, Δm 13 is the mass Mechanics, neutrinos can oscillate, namely change from one square difference between type 1 and type 3 neutrinos.

type to another during flight. This idea was very important If oscillation happens, Pee, to be measured as the ratio of since it is the most sensitive way to prove neutrinos are not observed neutrino events to that of expected, will be less massless. than 1. In addition, the observed neutrino energy spectrum Neutrino oscillations have three types as shown in Fig.1, will be distorted.

in which, the mixing angle θ23 denotes the so called atmos- Neutrinos from reactors can be detected by the liquid edited by edited by edited by by (INFN Pisa) Gordon Kane Dan Green Gordon L Kane Roberto Tenchini pheric neutrino oscillation; θ12 denotes the solar neutrino scintillator(made of CnH2n+2) via the following inverse & Aaron Pierce (Fermi National Accelerator Laboratory) (University of Michigan) & Claudio Verzegnassi oscillation. They have been measured by the Homestate, β-decay reaction: (University of Michigan) (University of Trieste) AD/PK/09/12/04/HC Super-K, SNO and KamLAND experiments to be non-zero, www.worldscientific.com – + namely neutrinos do oscillate. ν e + p → e + n.

September 2012, Volume 1 No 2 45 AD_PK_09_12_04_HC.indd 1 21/9/12 4:40 PM ARTICLES

The positron will lose its kinetic energy, which carries the Based on a detailed calculation and optimization, the information of neutrino energy, through ionization process plan is to built three experimental halls: the near Hall 1(EH1) and then annihilate with electrons, emitting two 511 keV γ’s. will house two identical neutrino detectors to monitor the The neutron will be slowed down via collisions with Daya Bay reactors, the near Hall 2(EH2) will house again two in the liquid scintillator and finally be captured by a proton identical neutrino detectors to monitor Ling-Ao reactors, with a capture time of 180 μs, releasing a 2.2 MeV γ. The and the Far Hall(EH3) will house four identical neutrino neutrino signal is then a coincidence of a prompt signal detectors to make a relative measurement with respect to from positron and a delayed signal from the neutron. Such the near detectors. All halls are connected by a 3100m long a coincidence scheme can significantly reduce backgrounds horizontal tunnel. Such a relative measurement can substan- from environmental radioactivity and cosmic-rays. In order tially reduce correlated systematic errors from reactors and to suppress further backgrounds, the liquid scintillator is detectors, while errors from backgrounds are suppressed by loaded with Gd to reduce the capture time and to increase the overburden of rocks and the shielding of detectors. energy released after the capture. In fact, neutron capture on The Daya Bay detector consist of two main sub-detectors: Gd can release 8 MeV γ’s and a 0.1% Gd-loading can reduce the Anti-neutrino detector, often referred as AD, and the the capture time to 28 μs, hence the coincidence window can muon veto detector, as shown in Fig.3. Anti-neutrino be substantially reduced. detector modules (AD) are immersed in the water pool to The Daya Bay neutrino experiment is proposed in 2003, be shielded from backgrounds. There are two ADs at each together with the other seven in the world. Daya Bay is near site and four ADs at the far site, allowing for cross advantageous among all the proposals since the nuclear checks between ADs at each site, and reducing uncorrelated power reactor complex is the second largest in the world and systematic errors. The water pool, equipped with photomul- moreover, there are mountains nearby so that underground tipliers is also a Cerenkov detector to tag cosmic-rays for laboratories housing neutrino detectors can be built easily vetoing. On top of the pool, there are four layers of Resistive to shield cosmic-rays. In fact, Daya Bay had a design of Plate Chambers (RPC) to track and tag cosmic-rays. Such a 2 sensitivity to sin 2θ13 of 0.01 at 90% Confidence Level(CL), detector design with multiple AD modules and multiple veto which is the best among all the eight. components can reduce significantly systematic errors and Since 80’s, there have been about 10 reactor experiments ensure enough redundancy for neutrino detection, muon with a baseline (distance between the reactor and the veto and background rejection. This is an innovative design detector) from 20m to 200 km and a weight from tens kg since it can reduce not only the systematic error, but also to 1 kt. They all have a precision of about (3-6)%, while the reduce the risk and simplify difficulties for the construction, design goal of Daya Bay is 0.5%. Special designs, as illustrated handling and transportation. in Fig. 2, are introduced to reach such a target.

Fig.2. Arrangement of the Daya Bay experiment, including two near Fig.3. Schematics of the Daya Bay detector: Anti-neutrino detector experimental halls(EH1 and EH2), and one far experiment hall(EH3). modules immersed in water, the water pool is equipped by photomulti- All halls are connected by a 3100m long horizontal tunnel. D1-D2 and pliers as the muon veto detector and the background shielding. At the top L1-L4 denote reactors. of the water pool, there are RPC modules served as muon veto detector.

46 Asia Pacific Physics Newsletter ARTICLES

Each AD module, as shown in Fig. 4, is designed to be for example, large thin shell low radioactivity stainless steel a cylinder with an outer diameter of 5m and the height of tanks, large thin shell acrylic vessels, 5m diameter end- 5m, filled with 3 types of liquid, separated by acrylic vessels. flange and its vacuum seal, 4.6m diameter reflectors, and in The inner-most acrylic vessel, 3m in diameter and 3m high, particular, the Gd-Loaded liquid scintillator. is filled with Gd-Loaded liquid scintillator as the neutrino Liquid scintillator(LS) is the heart of the experiment and target and the detection material. The middle layer, often technically difficult. Past experience at 10t level shows that called γ−catcher with an outer dimension of 4m and height of Gd-loaded LS can deteriorate over time and loss transpar- 4m, is filled with the normal liquid scintillator for improving ency. A new recipe was finally formulated and the chemical energy resolution at the edge of the target. The outer-most procedure was determined at the Institute of High Energy layer between the acrylic vessel and the stainless steel vessel physics(IHEP). Test results show that there is no observable is the mineral oil to shield γ backgrounds from steel and aging effect while the light yield and transparency exceed PMTs. Each AD is equipped by 192 8" PMTs arranged in the expectation. The mass production of 185t Gd-loaded 8 rows on the side walls of the cylinder. At the top and the LS is another challenge, both on the quality control and the bottom, there are no PMTs but reflectors made of ESR film production capacity. The whole production equipment was embedded in two acrylic sheets. The effective photocathode designed and manufactured by IHEP engineers with helps coverage is improved by a factor of two with such a design from industry. It is fully assembled and tested at IHEP and of reflectors. The total weight of a filled AD is about 110t, the actual production of LS was taken place at Daya Bay. in which Gd-Loaded LS is 20t, normal LS 20t, mineral oil Special care was taken for the raw material procurement, 40t, the stainless steel vessel 20t, and other components 10t. shipping and storage at such a large quantity with stringent cleanness and chemical compatibility requirements. The detector assembly started in 2010 when detector components are all available. A surface assembly building with a class 10K clean room was built right next to the tunnel entrance. AD modules are assembled in pairs in the clean room, and the sequence is showed in Fig.5.

Fig.4. The Anti-neutrino detector module.

The Daya Bay experiment was approved in 2006 by various Chinese funding agencies, and soon after by other international partners. The civil construction was inaugu- rated in Oct. 2007 and run at the full speed in 2008. The total length of the tunnel is 3100m with a typical dimension Fig.5. Assembly sequence of an AD module of 6.2m in width, and 7.2m in height. There were a total of about 3000 blasts right next to operational reactor cores. In The completed AD pair was fully tested and then trans- fact, no one exceeded the vibration limit of 0.007g monitored ported to the underground liquid scintillator hall for filling. at critical locations such as the top of reactors, set by the Attention should be taken during the filling to ensure: 1) Chinese Nuclear Safety Bureau. equal liquid levels(<5cm) among three volumes of the AD; 2) The detector construction started in parallel with the equal temperature(< 1oC) of three liquids to be filled into the civil construction, and had a number technical challenges, AD; 3) the target liquid mass is accurately measured to within

September 2012, Volume 1 No 2 47 ARTICLES

0.1%. The filling system was designed and fully tested at the are taken using LED and radioactive sources in the Univ. of Wisconsin at Madison, and then shipped to Daya detector; Bay. The filled AD will then be moved to the experimental 2) Event selection: By rejecting backgrounds using a hall for installation. set of selection criteria based on studies of data and The AD module is craned to the supporting stand in the Monte Carlo simulation, neutrino events from reac- water pool and to be connected to electronics cables and tors are selected for physics analysis; gas pipes. The water pool is already lined by PermaFlex and 3) Quantitatively analyze and determine backgrounds, PMTs are mounted to the supporting structure made of selection efficiencies and their uncertainties; stainless steel unistrut which are fixed to the wall. The inner 4) Calculate expected neutrino flux and energy spectrum and outer water pools are partitioned by tyvek sheets laid on from reactors taking into account the target mass and the PMT supporting structure. baseline; Once all of these are finished and everything is cleaned, deionized pure water is filled in the pool, as shown in Fig. 6. 5) Based on the neutrino spectrum measured at the The pool is then sealed by a light-tight and gas-tight cover near and the far detector, together with expectations, and the detector becomes operational. the disappearance of neutrinos from reactors can be determined and the conclusion of the neutrino oscillation can be given. Based on the first 55 days of data taken from Dec.24, 2011 to Feb.14, 2012, we observed that there is about 6% deficit of neutrinos at the far site comparing to the expectation(weighted average) from measurements at near sites, as shown in Fig.7. The deficit can be expressed as the ratio of observed neutrino events to that expected,

R = 0.940 ±0.011 (stat) ±0.004 (syst).

In addition, this deficit is not uniform cross the whole range of the energy spectrum, but peaked at about 3 MeV, as shown in Fig.7. Such a distortion is in agreement with Fig.6. Anti-neutrino detectors(AD) are immersed in water. neutrino oscillations. In fact, the experiment is designed to see such a distortion with maximum statistical significance The Daya Bay near hall(Hall 1) detector installation by a right choice of the detector baseline. was completed on Aug. 15, 2011 and neutrino signals are observed on the same day. The detector operation conditions are adjusted based on the detector calibration and the stable operation with all parameters fixed started on Sep.23. Event reconstruction and Monte Carlo tuning are performed so that neutrino events can be quantitatively measured. The Ling-Ao near hall(Hall 2) started data taking on Nov.5, 2011 while the Far hall(Hall 3) completed detector installation on Dec.24, 2012 and became operational immediately using parameters from other halls. This is also the day we start to take physics data for neutrino oscillation analysis with all three halls operational. Data analysis of neutrino events consists of the following steps: 1) Calibration: the detector response will be converted Fig.7. Observed neutrino energy spectrum at far site, as compared to the expectation(weighted average) from measurements at near sites. The to physics quantities such as the time and energy bottom panel shows the ratio of the two. The distortion of the energy through calibration processes. Special calibration data spectrum at far site is consistent with the neutrino oscillations.

48 Asia Pacific Physics Newsletter ARTICLES

If the disappearance of electron anti-neutrinos from The first observation of the non-zero13 θ is actually a reactors are explained by the neutrino oscillation, the oscil- discovery of new type of neutrino oscillation. It completes lation amplitude is determined, through a comprehensive our understanding of neutrino oscillation and deepened χ2 analysis, to be: our understanding of the fundamental principles. The observed oscillation amplitude is much larger than what we 2 sin 2θ13 = 0.092 ± 0.016(stat.) ± 0.005(syst.), anticipated, allowing for the planning of the next genera- tion neutrino experiments, in order to determine the mass as shown in Fig.8. The statistical significance of non-zero hierarchy and the CP phase. 2 -7 sin 2θ13 is 5.2σ, corresponding to a probability of 10 for A number of new experiments are planned now in the being a statistical fluctuation. world, based on neutrino beams from accelerators, as well as the one by our group for a next generation reactor neutrino experiments. We believe that study of neutrino physics will bring us a lot of new discoveries, and the picture of neutrino oscillation will be completed in the next 20 years.

Further reading: (1) F.P. An et al., Daya Bay Coll., “A side-by-side comparison of Daya Bay anti-neutrino detectors”, Nucl. Inst. and Meth. A 685 (2012)78 (2) F.P. An et al., Daya Bay Coll., “Observation of electron anti-neutrino disappearance at Daya Bay”, Phys. Rev. Lett. 108 (2012) 171803

Yifang Wang is the director of the Institute of High Energy Physics, Fig.8. Ratio of observed neutrino events to that of expected as a function Chinese Academy of Sciences. of baseline. The red line is the prediction of neutrino oscillation. The top- 2 2 right panel shows the χ as a function of sin 2θ13. Clearly at the minimum, 2 the best value of sin 2θ13 is given.

World Scientific Connecting Great Minds

by Martinus J G Veltman by Kerson Huang by Hans G Börner (Institut Laue by Lev Okun (Nobel Laureate in Physics, University of (Massachusetts Institute of Technology) Langevin) & Friedrich Gönnenwein (Institute of Theoretical and Michigan, Ann Arbor & NIKHEF) (University of Tübingen) Experimental Physics (ITEP)) AD/JK/09/12/02/HC www.worldscientific.com

September 2012, Volume 1 No 2 49 AD_JK_09_12_02_HC.indd 1 21/9/12 4:40 PM PEOPLE My Life as a Boson: The Story of “The Higgs”

Peter Higgs Department of Physics and Astronomy, University of Edinburgh, Scotland

he story begins in 1960, when Nambu, inspired by the BCS theory of superconductivity, formulated chirally invariant relativistic models of interacting Tmassless fermions in which spontaneous symmetry breaking generates fermionic masses (the analogue of the BCS gap). Around the same time Jeffrey Goldstone discussed sponta- neous symmetry breaking in models containing elementary scalar fields (as in Ginzburg-Landau theory). I became interested in the problem of how to avoid a feature of both kinds of model, which seemed to preclude their relevance to the real world, namely the existence in the spectrum of massless spin-zero bosons (Goldstone bosons). By 1962 this feature of relativistic field theories had become the subject of the Goldstone theorem. In 1963 Philip Anderson pointed out that in a super- conductor the electromagnetic interaction of the Goldstone My letter on how to evade the Goldstone theorem was mode turns it into a "plasmon". He conjectured that in accepted by Physics Letters. But when, a week later, I sent relativistic models "the Goldstone zero-mass difficulty is them a second letter outlining the simplest relativistic model not a serious one, because one can probably cancel it off in which spontaneous symmetry breaking generates a vector against an equal Yang-Mills zero-mass problem." However, boson mass (the Higgs model), it was rejected. It was at since he did not discuss how the theorem could fail or give this point that "Higgs bosons" made their first theoretical an explicit counter example, his contribution had little appearance; my revised version of the second letter (which I impact on particle theorists. If was not until July 1964 that, sent for publication to Physics Review Letters) drew attention following a disagreement in the pages of Physics Review to "incomplete multiplets of scalar and vector bosons" as a Letters between, on the one hand, Abraham Klein and Ben characteristic feature of non-Abelian generalizations of the Lee and, on the other, Walter Gilbert about the technical model. This version was accepted, and the referee (Nambu, details of the Goldstone, Salam and Weinberg proof of the as I learnt when I met him in 1984) brought to my attention theorem, it suddenly occurred to me that the ingredient that the related work of Brout and Englert. is crucial for evading the theorem is local gauge invariance. The controversy over the Goldstone theorem did not This is because gauge freedom complicates the implementa- end with the publication of my two letters. Gilbert raised tion of Lorentz invariance. technical objections, which I was unable to answer until,

50 Asia Pacific Physics Newsletter PEOPLE

at Chapel Hill in 1965, I had studied my Abelian model in By 1976, when LEP was being planned, this had been more detail. The resulting preprint led to an invitation from introduced to experimentalists in "a phenomenological Dyson to give a talk at the Institute, Princeton in March 1966; profile of the Higgs boson" by John Ellis, Mary K. Gaillard there I confronted an audience containing axiomatic field and Dimitri Nanopoulos. Apologizing for the vagueness of theorists whose belief in the Goldstone theorem was based this profile, they concluded "we do not wish to encourage on the vigorous algebraic proof by Kastler, Robinson, and big experimental searches for the Higgs boson, but we do Swieca. The next day Stanley Deser had arranged for me to feel that people performing experiments vulnerable to the talk at Harvard, where an equally skeptical audience awaited Higgs boson should know how it may turn up" . and; Sidney Coleman told me (in 1989) that they "had been Fifteen years later, with much of the Standard Model veri- looking forward to tearing apart this idiot who thought he fied experimentally, John Gunion, Howard Haber, Gordon could get around the Goldstone theorem". Kane, and Sally Dawson in "The Higgs Hunter's Guide" felt My Princeton and Harvard seminars succeeded in able to be more assertive: "The success of the Standard Model convincing people that I was not a crackpot, but they clearly has been astonishing. The central problem today in particle failed to persuade them that the combination of gauge physics is to understand the Higgs sector". theories and spontaneous symmetry breaking might be From 1989 onward measurements at LEP defined the useful. At Harvard, Shelly Glashow complimented me after parameters of the Standard Model with ever increasing preci- the seminar on "a nice model", but he did not see that this sion. Once the top had been discovered at Fermilab, might be the cure for the difficulties of his 1961 electroweak the fit between experiment and theory at one-loop level model. That was left to Weinberg and Salam the following depended only (logarithmically) on the Higgs mass(es). The year. Meanwhile, Brout, Euglert and I tried fruitlessly to predicted mass range indicated that a Higgs boson might be find an application in hadronic flavour symmetry breaking. within the reach of LEP's last run. As is well known, some It was in 1972, following the Veltman-'t Hooft proof of promising events were seen at around 115 GeV in the last the renormalizability of gauge theories, that my life as a week before LEP closed in the Fall of 2000. Now it is for boson really began. At the international HEP conference Fermilab to continue the search for "Physics' most-wanted at Fermilab that summer Ben Lee, reporting on the gauge particle." theory bandwagon which had began to toll, attached my name to everything involving spontaneous symmetry This is a reproduction with permission of the article origi- breaking, including the "Higgs meson". nally published in International Journal of Physics A.

World Scientific Connecting Great Minds

edited by Jennifer A Thomas by Nirmala Prakash by Harald Fritzsch by Ernest M Henley & Patricia L Vahle (formerly Visiting Professor at (University of Munich) & Alejandro Garcia (University College London) Massachusetts Institute of Technology) (University of Washington) AD/JK/09/12/03/HC www.worldscientific.com

September 2012, Volume 1 No 2 51

AD_JK_09_12_03_HC.indd 1 21/9/12 4:40 PM HISTORY Scientific Achievements of Prof. Chien Shiung Wu

Tan Lu (T. Lu) Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing 210008, China

I. Introduction Five years ago, we wrote two papers in memory of Prof. Chien Shiung Wu [1-2]. And now in memory of her 100th birthday, I am very happy to write this paper again. Indeed, she is a world top-class female experimental nuclear physicist. She is also known as the Chinese Madame Curie. As is well known, Madame (Marie) Curie was the first in discovering the radioactive substances, while C. S. Wu was the first in thor- oughly studying β-decay, the most mysterious one among radioactivities. C. S. Wu did various experiments in proving the Fermi’s theory of β-decay carefully and precisely, and even also improving it precisely and perfectly, and leading to the correct V-A form of the β-interaction and even leading to C. S. Wu and Luke C. L. Yuan the electro-weak unification finally. Indeed, C. S. Wu known as Chinese Madame Curie is reasonable and admirable. As generated from the uranium fissions on the neutron absorp- compared with Madame Curie, E. Segrè (1980) even said that tion, these effects made an important contribution to the C. S. Wu is more worldly, elegant, and witty [3]. “Manhattan Project”. She got her PhD in 1940. In March, C. S. Wu was born on 31 May, 1912, in Liuhe of 1944, C. S. Wu entered the Columbia University with the title Taicang City, Jiangsu Province, China. In 1934, she was of senior scientist and after doing a series of great experi- graduated from the Central ments in verifying Fermi’s theory of β-decay, she became an Univercity in Nanjing, China. associate professor in 1952. After making great contributions In 1936, she went to US and in her first discovery of the parity violation in β-decay of was admitted to the Univer- 60Co, she was promoted to be a full professor and elected as a sity of California in Berkeley, member of the US National Academy of Sciences in 1958. In became E. O. Lawrence’s and the same year, she received an honorary doctor degree (first E. Segrè’s student. Based on her time for a female) from Princeton University. In 1964, she two successful experiments, one won the Comstock Prize from the US National Academy of related with X-ray emissions Sciences. In 1972, she was appointed to be a Pupin professor after the β-decay of radioactive in Columbia University until she retired in 1980. Meanwhile, elements, and the other related in 1975, she became the first female president of American C. S. Wu in 1970s with the effects of Xenon gas Physical Society and received the National Medal of Science 52 Asia Pacific Physics Newsletter HISTORY

interaction, he considered the electron and the neutrino first coupled into a vector current (like a photon in the electro- magnetic coupling), and this leptonic vector current then coupled to the nucleonic vector current (neutron-proton vector current). This is a new kind of interaction in current- current direct coupling. Later, in 1935, E. J. Konopinski and G. E. Uhlenbeck proposed another theory with derivative coupling. C. S. Wu concentrated her research on the β-decay [5]. At that time, people had measured the β-spectra, but they found their measurements could not agree to Fermi’s theory. Especially, there were evident low energy electron excesses even for the simplest case of allowed spectra (Wu, 1950). C. S. Wu collaborated with R. D. Albert [6-7], success- fully prepared their radioactive sources uniform and thin enough, carefully measured the β-spectra of 64Cu and the In 1990, the asteroid with the international No. 2752 Purple Mountain Observatory discovered was named as “C. S. Wu’s Star”. low energy electron excesses were then eliminated clearly. After these careful preparations, their experiments agreed in the White House from the former US president G. Ford. to Fermi’s allowed spectra very excellently, and ruled out In 1990, in recognition of her great scientific achievements, the Konopinski-Uhlenbeck theory. However, in order to the asteroid with the international No. 2752 Nanjing Purple check Fermi’s theory thoroughly, various orders of forbidden Mountain Observatory discovered, was named as “C.S. β-spectra, especially the unique forbidden ones, should also Wu’s Star”. In 1991, she was granted the Pupin Memorial be carefully measured. C. S. Wu and her collaborators did Medal which represents high honor in the world of science all these experiments and checked the Fermi’s theory in and engineering. In 1994, she was elected as one of the first detail. Experiments also showed that the Fermi’s theory in its foreign academicians of Chinese Academy of Sciences. She original sense with only vector current (obeying the Fermi was also awarded honorary professorships or granted with rule) is not enough. Other kinds of currents obeying the honorary doctor degrees at more than 20 universities [4]. Gamow-Tellor rule should also exist. Indeed, there is not a priori reason to keep only vector current, otherwise, people should use the linear combination of all 5 possible currents: V II. Pioneer work in β-decay (vector), S (scalar), T (Tensor), A (axial vector) and P (pseudo We know, radioactivities include three kinds, α-decay, scalar). Before the discovery of parity violation, people had β-decay and γ-decay. Among these, the β-decay is the most been misled to the conclusion of the linear combination of mysterious, most complicated and also most important one. T and S. We will see later, the parity violation would soon In β-decay, an electron or a positron will be emitted from lead to the correct combination of V and A. a radioactive nucleus. However, a nucleus is composed of protons and neutrons, neither electrons nor positrons exist within a nucleus originally. And the electrons or positrons emitted in β-decay did not have fixed energies, they show a continuous spectrum. This feature even led to suggest non-conservation of energy happening there. In order to save energy conservation, W. Pauli proposed an additional neutral particle “neutrino” with almost zero mass and spin 1/2 also emitted accompanying the electron. In 1934, based on Pauli’s neutrino hypothesis, E. Fermi formulated a new theory for β-decay with 4-fermion (for example, neutron, proton, electron and neutrino) direct coupling. He assumed an electron and a neutrino (really an anti-neutrino) simultaneously produced during a neutron transforming into a proton. Similar to electromagnetic W. Pauli and C. S. Wu

September 2012, Volume 1 No 2 53 HISTORY

III. First experiment showing parity violation in parity non-conservation on 1st October, 1956 [12], still no β-decay experiments were undertaken to check the question of parity non-conservation immediately. However, C. S. Wu was the β-decay is a typical radioactive decay process with weak unique person, she believed that it would be worthwhile to interaction. However, at that time, people had already test such a fundamental law even if the parity conservation known a lot of decay processes with weak interactions in law was as usually believed to be proved correct, so she put particle physics, such as π+ → μ+ + ν , μ+ → e+ + ν + -ν , K+ → μ e μ her whole heart into the preparation of such an experiment π+ + π0, θ+ → π+ + π0, τ+ → π+ + π+ _ π–, Λ0 → p + π– and others. [13]. And the famous theoretical physicist W. Pauli was even Were all these processes decaying with same strength of ready to bet a very high sum that the experiment would give interactions? O. Klein (1948) [8]; T. D. Lee, R. Rosenbluth, right-left symmetric results in his letter to another famous C. N. Yang (1949) [9]; G. Puppi (1949) [10]; J. Tiomno, J. theoretical physicist V. Weisskopf [4]. A. Wheeler (1949) [11] almost simulteniously studied this problem and pointed out that all these processes decay with similar strength. This fact strongly means that there should be a unified interaction, maybe named as the weak interac- tion. Therefore, in the world, there are clearly only four interactions, namely gravitational, electromagnetic, weak and strong interactions, here the means the force keeping protons and neutrons together in a nucleus. Here, τ and θ appeared to be very strange. As π is a particle with negative parity, if parity obeys conservation law, then θ should be with positive parity, while τ with negative parity. Thus, τ and θ should be different particles. However, people find their mass and lifetime are exactly identical. These facts are difficult to explain. T. D. Lee and C. N. Yang thought, these two particles might be just one C. S. Wu and her Collaborators from National Bureau of Standards in same particle, and parity here might be not conserved [12]. Washington DC Then, they investigated all kinds of nuclear and particle → . → experiments and tried to find, were there any experiments C. S. Wu chose the pseudo-scalar p e σ N to measure in → 60 → that had ever been verified the parity conservation. They her experiment, here σ N is the spin of Co, and p e is the 60 concluded that only those experiments having ever measured momentum of the electron emitted from Co. In order → → → → → to do this experiment, she should arrange her radioactive a pseudo-scalar quantity, such as p . σ or p1 × p2 . p3 etc. (here 60 p→ denotes a vector; σ→ denotes an axial vector) , can definitely source highly polarized with almost all Co spin paralleled check whether parity being conserved or not. They indeed along one direction, and this high polarization could keep a found that parity had definitely been checked to be conserved relatively long time only under the condition of very strong in strong and electromagnetic processes. However, they magnetic fields and ultra-low temperature down to about excitingly found [12], in fact no experiment had ever been 0.01° K. She collaborated with E. Ambler, R. W. Hayward, performed to check whether parity is conserved or not D. D. Hoppes and R. P. Hudson from the National Bureau in weak interaction! But why almost everyone had been of Standards in Washington, D. C., where there were good misled into believing that parity had already been proved conditions for such a low temperature. They spent about to be conserved in many experiments in β-decay? The half a year to do this task, and finally discovered a large reason might be that parity conservation implies right-left difference in the counting rates of electrons emitted along the 60 symmetry, which should seem to be naturally true. Even direction of the Co spin and along the opposite direction 60 though many people did their measurements of the angular [13]. Let us put a mirror perpendicular to the Co spin, a distribution of emitted electrons, they usually only measured large right-left asymmetry can be seen evidently. Thus they one half of the electrons (for example, in the right direction), clearly discovered the parity non-conservation in β-decay and assumed the other half (in the left direction) could be for the first time [13]. determined just by right-left symmetry. Due to this strong In early 1957, another group (R. L. Garwin, L. M. belief, after Lee and Yang published their prediction of Lederman, and M. Weinrich) in Columbia University got

54 Asia Pacific Physics Newsletter HISTORY

C. S. Wu’s preliminary exciting results, and quickly did a Wu’s discovery of parity violation should definitely be one of + + + -muon-electron decay chain experiment: π →μ +νμ, μ the most important scientific discoveries in human history. + - →e + ν μ + νe [14]. For a rest pion, the emitted muon should People should also note that C. S. Wu’s very same experiment be polarized along its motion, then they could easily give out on parity violation did also disprove the conservation of the large asymmetric positron motion relative to muon. This charge conjugation. decay chain experiment was very simple and easy to do, only about “24 hours” can finish the experiment. Indeed, Garwin et al quickly did it and quickly wrote their paper. At that time, there were at least eight accelerator facilities capable of making pions, of which many could be competitors to do such “24 hours” experiment. So, Garwin et al were eagerly to publish their paper. However, they were also morally committed to publish together with C. S. Wu. But she, as a great scientist, was not going to rush her publication. Thus they were forced to wait an agonizing week until she satisfied herself that the 60Co results were solid. This is a true story Lederman [15] told during the International Conference on Physics since Parity Symmetry Breaking in Memory of Professor C. S. Wu, held in Nanjing in 1997. Lederman In 1978, C.S. Wu was awarded the first Israeli Wolf Prize in Physics, a further said: “the week of agony I endured some forty years prize also at the Nobel Prize level. ago at the hands of my esteemed colleague C. S. Wu taught me a lesson about what it means to be a great scientist. That is, that validity of your results must have the highest priority.” IV. Discovery of a New Conservation Law: the This story is also of great educational meaning for all of us, Conservation of Weak Vector Current (CVC) the younger generations. As we had seen that just prior to the discovery of parity viola- The discovery of the parity violation in weak interaction tion, C. S. Wu had done a lot of work in verifying the Fermi’s was of great importance that Lee and Yang were awarded theory accurately and precisely, only the true linear combina- the Nobel Prize for Physics very quickly, just in the very tion of 5 kinds of current couplings left to be determined. At same year. This scientific event is so important that why that time, the linear combination of the nucleonic currents C. S. Wu was not awarded the Nobel Prize became a big was misled to be containing T and S. However, the discovery and a half century long question. As there were very many of parity violation extended the combination greatly and experiments on parity violation done soon afterwards, one doubled its contents by including the parity nonconserved might that there were too many experimental couplings. Considering parity violation, we knew that the physicists connected with the discovery of parity violation emitted electron should be fully polarized (±ν/c) and the to be chosen to share the Nobel Prize with Lee and Yang. neutrino be completely left polarized. Using the measured However, among the first three groups related with parity β – ν angular correlation, we can rule out T and S. And in violation experiments, C. S. Wu group was clearly the first β-decay, P should be negligible. Then, only V and A do exist one. Garwin group began their experiment only after getting in the combination. Considering the β-decay of neutron, C. S. Wu’s preliminary results, while the third group of J. using the non-symmetric coefficients in the angular distribu- I. Friedman and V. L. Telegdi [16] began their experiment tion of electron and neutrino relative to the neutron spin, only after knowing results from Garwin’s group. All other people can determine the nucleonic current to be (V-1.2A). experiments began even much later. In fact, during the whole As neutrino is pure left handed, the leptonic weak current period of Wu’s parity experiment (half a year), no other can only be pure (V-A). The difference between the nucleonic experiments on parity did ever be arranged. The priority of current (V-1.2A) and the pure leptonic current (V-A) is not C. S. Wu should be no problem. The archives of the Nobel surprising, as the nucleonic current could be influenced by Prize may be released 50 years after an award, why C. S. Wu strong interaction (there should be renormalizing effects), haven’t been awarded the Nobel Prize might be answered while the influence being so small is indeed surprising! soon. However, in 1978, C. S. Wu won the first Israeli Wolf Especially please note that the influence happened only Prize, a prize also at the Nobel Prize level. Anyway, C. S. in the axial vector current, not in the vector current! R. P. September 2012, Volume 1 No 2 55 HISTORY

Feynman and M. Gell-Mann (1958) [17] suggested that observed evidence of the second class weak current. So, the weak vector current should be conserved, just as the Wu’s experiment of 1963 was doubted. Furthermore, the electric vector current, known as the conservation of vector Bhalla-Rose’s Fermi functions of β-decay used by Wu et al. current (shortly as CVC). It is very interesting to note that in their work were also doubtful. In 1977, C. S. Wu with as early as in 1955, S. S. Gershtein and I. B. Zeldovich had her collaborators [23] re-studied this problem carefully. As already proposed the conservation of weak vector current they used the Behrens-Janeoke’s refined Fermi functions [18]. However, at that time, people did not know any vector of β-decay instead of the Bhalla-Rose’s, they found that the component in the weak current! shape factor of β-decay from 12B-12N was indeed markedly Let us consider first the electromagnetic interaction, for changed, but they also found that when the refined data of example, consider a proton (p). As a proton is a , a branch ratio and ft value were used, the shape factor was particle with strong interaction, it can virtually go into a changed in the opposite way. These two changes exactly neutron and a pion, namely p → n + π+. Evidently, in the compensate each other, and the CVC still holds. Please virtual state, charge conservation (namely the electric vector note, many other experiments also definitely disproved the current conservation) guarantees the π+ to support the existence of the second class weak current. electromagnetic interaction originally given by p. Please note, In 1977, during the Tokyo International Conference the virtual state of n + π+ is not identical with the original on Nuclear Structure, Deutsch humorously applied the state p, at least it became bigger or fatter and with different title of Shakespeare’s drama “Much Ado About Nothing” inner structure or different magnetic moment. Similarly, let to describe the storm of the “possible existence of second – - us consider the weak process such as n → p + e + ν e, here n class weak current”. In response, C. S. Wu aptly quoted the can also go into a virtual state n → p + π –, the conservation of title of Shakespeare’s another drama “All’s Well That Ends weak vector current (CVC) also guarantees the π – to support Well” to describe the satisfactory and concordant ending – 0 – - the weak interaction: π → π + e + ν e (De Pommier et al. of that storm. 1963 [19]; Bacastow, 1962 [20]; Dunaltsev et al. 1963 [21]). And the renormalizing effects here could also make some V. Leading to the Quick Development of Particle different inner structure of the original decaying object or Physics its some different “weak-magnetic moments”. C. S. Wu, Y. K. Lee and L. W. Mo (1963)[22] chose the radioactive sources From the discovery of radioactivity (~1897) to the proposal 12B and 12N to test the conservation of weak vector current. of the Fermi theory of β-decay (1934), and to the discovery They compared the transitions experimentally from the of parity violation (Wu, 1957), there had been about 60 years. isospin triplet (spin-parity 1+: ground state of 12B, excited However, since the discovery of the parity violation there was state – 15.11 MeV of 12C, ground state of 12N) to the isospin only about one year for Feynman and Gell Mann (1958) to singlet (spin-parity 0+: ground state of 12C). One needed to propose the correct form (V-A) for the weak interaction. And measure and compare the shape correction factor of the even in the same paper, they also proposed the conservation β-spectra from 12B and 12N. Though this kind of experi- of the weak vector current. Five years later, by 1963, two – ment had been done earlier, but no definite conclusion had kinds of experiments (weak “charge” conservation: π → 0 – - been obtained. C. S. Wu and her collaborators in 1963 first π + e + ν e and “weak magnetic moment” produced by conducted this experiment successfully, and decisively veri- renormalizing effects) were independently done in verifying fied the conservation of weak vector current. This experiment the conservation of the weak vector current. This feature is very important and fundamental. They not only founded supported the electro-weak unification, which had been a new conservation law, but also built a mile-stone toward done successfully based on Yang-Mills field (1954) [24] the unification of weak and electromagnetic interaction. by Weinberg (1967) [25], Salam (1968) [26] and Glashow Either in the weak vector current or in the weak axial- (1961) [27]. In order to interpret the origin of particle mass, vector current there could be terms with different G-parities. P. Higgs (1964) proposed a boson named as Higgs boson G-parity means the combined operation of charge symmetry [28]. Several years later, D. Gross and F. Wilczek (1973) [29], and charge conjugation. The term in the weak current with and D. Politzer (1973) [30] made an important theoretical opposite G-parity relative to the usual term is called the discovery of asymptotic freedom in the theory of the strong second class weak current. C. S. Wu’s experiment in 1963 interaction. This is the , known on CVC disproved the existence of the second class weak as QCD. Now we have the electro-weak unification theory current. While in 1970’s, some people claimed to have and the QCD theory, already covered electromagnetic,

56 Asia Pacific Physics Newsletter HISTORY weak and strong interactions. These interactions can already VI. Scientific Achievements in Wide Fields completely describe the particle physics, as gravitational Apart from her three main achievements stated above, C. S. force is so weak that could only be applied to describe the Wu also had performed a lot of fundamental research work astrophysical phenomena. Then, only 16 years since the in rather wide field [4]. discovery of parity violation, based on Yang-Mills field, the As early as her graduate student days she studied two Standard Model for particle physics was established. On the projects. One was related with the continuous X-rays excited fundamental particle level, we now have 6 flavors of quarks by the beta particles of 32P. Her interest related with inner (u, d, s, c, b, t), every flavor quark has three colors, totally bremsstrahlung even led her to do a series work about the we should have 18 kinds of quarks. If including anti-quarks, electron capture on 37A, 55Fe, 131Cs, and 204Tl. These results had we should double the number to 36. And we also have 6 been cited and introduced in many text-books. The other was leptons (e–, μ–, τ–, ν , ν , ν ), and 6 anti-leptons (e+, μ+, τ+, -ν , e μ τ e related with 135Xe which she discovered in uranium fission -ν , -ν ). All these quarks and anti-quarks, leptons and anti- μ τ excited by low energy neutron. This135 Xe played a decisive leptons, are total 48 fermions with spin 1/2. Besides these, role in slowing down or even stopping the chain reaction in there are also various bosons which can charge interactions. the nuclear reactor in Washington. In this work, she made For strong interaction, there are 8 gluons; for electro-weak an important contribution to the “Manhattan Project”. interaction, they are W+, W–, Z0 bosons (Yang-Mills bosons) After her research on CVC, C. S. Wu began to study the and γ (photons); for gravitational interaction, that is one double β-decay [31]. For example, AN → AN + e– + e– + -ν + kind of gravitons. If including Higgs boson, we have totally Z Z+2 e -ν . If the lepton number is not conserved, the above process 62 kinds of fundamental particles. Up to now, within the e could also go through without neutrinos emitted: AN → AN standard model, 61 kinds of fundamental particles have been Z Z+2 + e– + e–. These two kinds of double β-decay would have very found, only the Higgs boson remains to be discovered. It is different lifetimes. In order to keep at very low background very interesting, just a few days ago (July 4, 2012), CERN level, such experiments should be done under deep salt mine. announced that they have found a new particle on the Large C. S. Wu did her double β-decay experiments on 48Ca and Hadron Collider (LHC) with mass between 125-126 GeV, 82Se, but never found neutrino-less double β-decay events. C. which is very similar to the Higgs boson. We would be very S. Wu then put the upper limit for lepton non-conservation happy to have this exciting news in memory of C. S. Wu’s at 3 × 10–4. 100th birthday. C. S. Wu and her collaborators systematically studied the exotic atoms. The exotic atom means the atom with one electron replaced by another negatively charged particle such as μ– , π– , K – , Σ– or -p (anti-proton). These particles are much heavier than the electron, so the Bohr radii of these exotic atoms are much smaller than the ordinary atom. In other words, in exotic atoms, these particles are much closer to the nucleus than in case of electron. Thus, for such exotic atoms the energy level splitting would be much larger than for usual atoms, so the emitted photons are usually in the X-ray bands. By measuring these X-rays one can study many nuclear properties. This is also a good way to study the interaction in detail between those particles and the atomic nucleus. In these studies, C. S. Wu obtained much better understanding about the properties and structures of the nuclei of muon, hadron or meson atoms [32]. C. S. Wu was also aware that the Mössbauer effect could provide an excellent and ultra-precise method for γ-ray measurements, she quickly applied it to her research and obtained a lot of important results [33]. As 57Fe is an important Mössbauer isotope and Fe is also an important C. S. Wu in her Laboratory element in Blood, she and her collaborators used this effect

September 2012, Volume 1 No 2 57 HISTORY successfully to solve various important biological questions related to blood. Using a 3He-4He dilution refrigerator to study the Möss- bauer spectra of FeNH4(SO4)2•12H2O, C. S. Wu and her collaborators found that there were interesting differences for cases with and without external magnetic fields. They [34] also studied the decay of polarized 110Agm under ultra-low temperatures, and demonstrated time reversal symmetry with a precision up to 10-3. C. S. Wu also paid a lot of attention at the fundamental questions of quantum mechanics. Just after the discovery of the Mössbauer effect, C. S. Wu exploited its high sensitivity, quickly prepared her experiment, clearly observed the 1990, C. S. Wu with T. Lu (author) uncertainty relation between energy and time, a fundamental At Pupin Building (Dept of Physics, Columbia Univ) relation in quantum mechanics. As is well known, the EPR (Einstein-Podolsky-Rosen) paradox [35] is the most penetrating example among the lifelong Einstein-Bohr debates on quantum mechanics. Originally, these debates were only philosophical and ideological. In 1964, J. S. Bell [36] proved an inequality (known as Bell inequality), which put the philosophical and ideological debate into a physical and experimentally determinable context, especially for the hidden parameter interpretation of quantum mechanics. Any kind of hidden parameter theory should obey the Bell’s inequality, while quantum mechanics could violate it. In 1975, C. S. Wu and her collaborators [37] used the β+-decay of 64Cu to measure the correlation between two polarized photons emitted from e+e– annihilation. Their results violated Bell’s inequality, but agreed with quantum mechanics very well. It is worthwhile to note that as early as in 1950, 14 1992, C. S. Wu, Luke C. L. Yuan with Editorial Board of ”Selected Papers years earlier than the Bell’s inequality published, they [38] and Lectures of C. S. Wu and Luke C. L. Yuan” had already performed a kind of correlation experiment on rear, from left: J. Fang, Y. F Hsia, Z. S. Sha, T. Qin, S. T. Bao front, from left: T. Lu, Luke C. L. Yuan, C. S. Wu, D. Feng which the above experiment was based.

story very deeply impressed us. VII. A Few Words Further Later, after I was working in Nanjing University, I had When learning physics in Peking University, I first heard met her for many times when she visited Nanjing. 1990, the name “C. S. Wu” from the book “Theoretical Nuclear when I visited New York, Prof. C. S. Wu invited me to visit Physics” by J. M. Blatt and V. F. Weisskopf, 1952 [39]. At that her and stay a whole day at her home. I was very fortunate time, she was already a famous experimental nuclear physi- to have many hours to talk with her and her husband Luke cist. After she finished her great discovery of parity violation C. L. Yuan. I learned very much about their rich experi- in β-decay of 60Co, very many laboratories, successfully did ences in scientific research. Their spirit of diligence, acuity, various experiments, and proved that the parity in weak insight and persistence was truly admirable; their concern interaction is definitely not conserved. From mid-January for the progress of China and the fostering of posterity was of 1957 on, just in the last year of my under-graduate studies inspirational. in Peking University, we could read almost everyday news 1992, D. Feng and T. Lu edited a book: “Scientific Careers about parity non-conservation from various laboratories all of Half a Century - Selected Papers and Lectures of Chien over the world. This situation lasted for more than half a year. Shiung Wu and Luke C. L. Yuan (in Chinese)”, published by So wonderful such an exciting history was? This scientific Nanjing University Press [4].

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C. S. Wu and Luke C. L.Yuan provided many schools, [18] S. S. Gershtein and I. B. Zeldovich, Zh. Eksperim. i Teor. universities and institutions with various kinds of support. Fiz. 29, 698 (1955). For example, Mingde School in Taicang, Jiangsu Province, [19] P. De Pommier, J. Heintze, C. Rubbia, et al. Phys. Lett., 5, 61 (1963). was originally established as an elementary school by her [20] R. Bacastow, T. Elioff, R., Larsen, et al. Phys. Rev. Lett., 9, father but under their support has now become a modern 400 (1962). and much larger school covering also secondary education. [21] A. F. Dunaltsev, V. I. Petrukhin, Yu. D. Prokoshkin, et al. In recognition of her contributions, the Library of the Physics Proc. Intern. Conf. Fundamental Aspects Weak Interac- Department in Nanjing University, a College of the Southeast tions, 1963. University, and many other institutions have been named [22] Y. K. Lee, L. W. Mo, and. C. S. Wu, Phys. Rev. Lett. 10, 253 (1963). after her. The couple also donated almost their whole life’s [23] C. S. Wu, Y. K. Lee, and. L. W. Mo, Phys. Rev. Lett. 39, 72 savings to establish a foundation for Nanjing University (1977). and Southeast University to invite renowned physicists to [24] C. N. Yang and R. L. Mills, Phys. Rev., 96, 191 (1954). lecture there yearly. Their contributions will indeed benefit [25] S. Weinberg, Phys. Rev. Lett., 1967, 19, 1264 generation after generation. [26] A. Salam, in elementary particle physics II Nobel Symp, 1968, 8, 367 [27] S. Glashow, Nucl. Phys., 1961, 22, 579 [28] P. Higgs, Phys. Rev. Lett., 1964, 13, 508 Lu Tan is a member of Chinese [29] D. Gross, F. Wilczek, Phys. Rev. Lett., 1973, 30, 1343 Academy of Sciences (CAS), [30] H. Politzer, Phys. Rev. Lett., 1973, 30, 1346 working at the Purple Mountain [31] C. S. Wu, AIP Conference Proceedings 96, 374 (1983). Observatory, CAS. [32] C. S. Wu, Vol. 3, ed. Smith and Walters. [33] C. S. Wu, Y. K. Lee, N. Benczer-Koller, and P. Simms, Phys. Rev. Lett. 5, 432 (1960). [34] G. W. Wang, A. J. Becker, L. M. Chirovsky, J. L. Groves, and C. S. Wu, Phys. Rev. C 18, 476 (1978). References [35] A. Einstein, B. Podolsky, and N. Rosen, Phys. Rev. 47, 777 [1] T. Lu and F. Wang, AAPPS, 17, 10-14 (2007). (1935). [2] T. Lu, Physics, 36, 681-686 (2007). [36] J. S. Bell, Physics 1, 195 (1964). [3] E. Segrè, From X-rays to Quarks, W. H. Freeman and [37] L. R. Kasday, J. D. Ullman, and C. S. Wu, IL Nuovo Cimento Company, New York (1980) 253, 633 (1975). [4] D. Feng, T. Lu, eds., Scientific Careers of Half a Century, [38] C. S. Wu and I. Shaknov, Phys. Rev. 77, 136 (1950). Selected Papers and Lectures of Chien-Shiung Wu and Luke [39] J. M. Blatt and V. F. Weisskopf, “Theoretical Nuclear C. L. Yuan (in Chinese), Nanjing University Press (1992). Physics”, New York-London, 1952. [5] C. S. Wu, Rev. Mod. Phys. 22, 386(1950). [6] C. S. Wu and R. D. Albert, Phys. Rev. 75, 315 (1949). [7] C. S. Wu and R. D. Albert, Phys. Rev. 75, 1107 (1949). [8] O. Klein, Nature, 161, 897 (1948). [9] T. D. Lee, R. Rosenbluth, C. N. Yang, Phys. Rev., 75, 9905 (1949). [10] G. Puppi, Nuovo Cimento, 6, 194 (1949). [11] J. Tiomno, J. A. Wheeler, Rev. Mod. Phys., 21, 153 (1949). [12] T. D. Lee and C. N. Yang, Phys. Rev. 104, 254 (1956). [13] C. S. Wu, E. Ambler, R. W. Hayward, D. D. Hoppes, and R. P. Hudson, Phys. Rev. 105, 1413 (1957). [14] R. L. Garwin, L. M. Lederman, and M. Weinrich, Phys. Rev. 105, 1415 (1957). [15] L. M. Lederman, Proceedings of the International Confer- ence on Physics since Parity Symmetry Breaking in Memory of Professor C. S. Wu, ed. F. Wang (World Scientific, Singapore, 1998), p. 611. [16] J. I. Friedman and V. L. Telegdi, Phys. Rev. 105, 1681 (1957). [17] R. P. Feynman and M. Gell-Mann, Phys. Rev. 109, 193 (1958).

September 2012, Volume 1 No 2 59 HISTORY Satyendra Nath Bose – His Life and Times

Kameshwar C. Wali Department of Physics Syracuse University, USA

Never accept an idea as long as you are yourself not satisfied with its consistency and the logical structure on which the concepts are based. Study the masters. Those are the people who have made significant contributions to the subject. Lesser authorities cleverly bypass the difficult points. Satyendra Nath Bose

onsidering Bose’s legendary association with Einstein and a remarkable discovery to his credit, one might expect him to be better known in the international Csphere. However, little is known about him outside India. Quite often he is thought to be from Germany, name misspelt without the “umlaut” on “o”. Even in India, he is often confused with Jagadish Chandra Bose, who was the first 19th century scientist from the country to have received worldwide recognition for his experiments on wireless trans- mission as well as his experiments with plants, demonstrating such vital characteristics in them as growth, nervous system and other distinguishing features of animal life. The first quarter of the th20 century was indeed a golden period in the history of India, and the province of Bengal in particular. Considered more progressive than other provinces, it was the first to accept and adopt British ways of life and literature. Bengal was also the first to rebel against the colonial masters, especially, when in 1905 (coincidentally the Einstein miracle year), Lord Curzon partitioned Bengal into two, West and East Bengal to curb the rising nationalist movement. Bose, a brilliant student throughout his career, joined a group of accomplished intellectuals motivated strongly to excel in arts and sciences and other creative endeavors to demonstrate their national fervor and to prove that they were competitive with their counterparts in the western world. ❊ ❊ ❊

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up laboratories — to teach advanced courses for B.Sc. honors and M.Sc. students. He taught thermodynamics and Maxwell’s theory of . The library was just being replenished with books and journals. And just as his first group of students was graduating in 1923, he received notification that his appointment could not be extended beyond a year. A conflict between the government of India and the provincial Government of Bengal had resulted in the cut-off of funds for the university. Bose became involved in a long struggle with the university to keep his appointment. It was under such troubled circumstances that he wrote his famous paper and sent it for publication in late 1923 or the beginning of 1924 to Philosophical Magazine. Six months later, when the editors of the journal informed him that (regrettably) the referee’s report on his paper was negative, he sent his rejected paper to Einstein with an accompanying letter (See Fig. 1), which Begins2

Bose at Daka University c. 1930s Respected Sir,

I have ventured to send you the accompanying article In 1919, soon after the war ended and Einstein’s theory for your perusal and opinion. I am anxious to know received worldwide acclamation due to the confirmation of what you think of it. You will see that I have tried one of its predictions, namely, the deflection of light due to to deduce the the coefficient 8πν2 /c3 in Planck’s law gravitational field, the young self-taught stalwarts took upon independent of the classical electrodynamics only themselves the translation of the original papers on special assuming that the ultimate elementary regions in and general relativity. Bose and Saha’s book was the first such the phase space has the content h3. I do not know collection in English.1 sufficient German to translate the paper. If you think Satyendra Nath, like other aspiring young scientists, the paper is worth publishing, I shall be grateful if you was eager to go abroad to Europe, but he was not fortunate arrange for its publication in Zeitscrift für Physik. enough for one reason or the other to acquire such an Though a complete stranger to you, I do not feel opportunity. Being married was one of his obstacles. His any hesitation in making such a request. Because friend and colleague Saha was more enterprising. He was we are all your pupils though profiting only by your awarded the Doctor of Science degree of Calcutta University teachings through your writings. and on that basis won a scholarship to go abroad. In the mean time, while teaching thermodynamics and astrophysics, Yours Faithfully, Saha got interested in thermal ionization and developed the S.N. Bose celebrated Saha’s theory of high temperature ionization and its consequences in astrophysics. The scholarship afforded Einstein’s reply came in a postcard dated 2 July 1924 him the opportunity to work in the laboratories of A. Fowler (Fig. 2) in which he wrote, “I have translated your paper in London and Herman Walther Nerst in Germany to verify and given it to Zeitscrift für Physik for publication. It signi- his theory. fies an important step forward and pleases me very much.” In 1921, Bose got an offer of a Readership at a higher In a note appended to his translation and published with salary in the newly established university in Dacca in East the paper, Einstein says that Bose’s derivation “appears to Bengal (presently called Dhaka University, that is now me an important step forward. The method used here also in Bangladesh). The Vice Chancellor of the University, yields the quantum theory of an ideal gas, as I shall show P.l. Hartog, was a visionary committed to excellence. He elsewhere.” Indeed, on 10 July 1924, within a week or so after hand-picked Bose, who soon found himself with the task receiving Bose’s paper, Einstein presented his own paper to of building a whole new department — including setting the Prussian academy. Titled “On the Quantum Theory of

September 2012, Volume 1 No 2 61 HISTORY

Figure 1. Satyendra Nath Bose in Paris in 1925. It was Figure 2. In July 1924, sent S. N. Bose a from Dacca in 1924 that Bose sent Einstein this letter postcard (left) that accepted Bose’s paper on radiation accompanying his manuscript on Planck’s blackbody statistics and acknowledged its importance. (Card from radiation law. (Photo courtesy of Falguni Sarkar; letter ref. 4; 1920s photo of Einstein courtesy of AIP Emilio from ref. 3) Segré Visual Atchives.)

62 Asia Pacific Physics Newsletter HISTORY

Monoatomic Gas,” it was an extension of Bose’s work. He followed up that paper with two more in 1925, the second of which is well known for its prediction of a possible new state of matter whose existence took 70 additional years to demonstrate — the Bose-Einstein condensate. Bose’s successful derivation of Planck’s law and Einstein’s recognition of its importance is one of the most exciting episodes of the 20th century physics. It has all the twists and turns and ironies of failed attempts on the part of some of the great physicists of the period and the success of a relatively unknown young man from Dacca University in East Bengal. It involved a great struggle on many profound philosophical issues associated with the fundamental nature of matter and radiation. I will not dwell here on this history S. N. Bose in 1953. (Courtesy of Etienne Eisenmann.) and its subsequent developments since it is the subject matter of several papers in this volume. Returning to Bose’s life, Einstein’s 2 July postcard had a tremendous impact on his Reference: life and career. It was influential enough for him to obtain 1 The Principle of Relativity, The Original Papers by A. a two-year study leave in Europe. He had applied for such a Einstein and H. Minkowski, translated into English by M.N. fellowship in January, but he had not received any response. Saha and S.N. Bose with a historical Introduction by P.C. Mahalanobis, University of Calcutta 1920. But as soon as the Vice Chancellor saw the postcard, the problem was solved. As Bose says 2 There are conflicting accounts regarding the sequence of events that led Bose to send the manuscript of his first paper That little thing [Einstein’s postcard] gave me a sort to Einstein. My account is based on those of W. A. Blanpied of passport for the study leave for two years with a and John Stachel. See the articles, Satyendra Nath Bose: good stipend, a separation allowance for the family, Co-Founder of Quantum Statistics by W.A. Blanpied and Einstein and Bose by John Stachel included in this volume. sumptuous travel allowance with a round trip fare.5 3 The Early Phases of My Exploration in Science, S. N. Bose, He also got a visa from the German consulate just by (The Man and His Work, Part II, p.246), S. N. Bose National showing them Einstein’s postcard. No fee required! He left Center for Basic Sciences, Calcutta (1994). for Europe in early September aboard a steamer of the Lyod Triestino Line and arrived in Paris in 18 October 1924. 4 Bose Statistics: A Historical Perspective. Partha Ghose (The Man and His Work, Part I, pp.35), S. N. Bose National Center for Basic Sciences, Calcutta (1994). Reproduced from the book, Satyendra Nath Bose — His Life and Times (Selected Works with Commentary), edited by 5 The Golden Age of Theoretical Physics, Jagdish Mehra, Kameshwar C Wali, World Scientific, pp.xv-xxii. (World Scientific, 2001) p. 514.

Kameshwar Wali is the distinguished research professor emeritus at the Department of Physics at Syracuse University, USA

September 2012, Volume 1 No 2 63 BOOKS

MADAME CHIEN-SHIUNG WU was nicknamed “The Chinese Madame Curie” in the early days. In my interviews preparing for this book, many great The First Lady of Physics scientists, including many foreign Nobel Laureates, say that Wu may have made greater contributions to physics than Research Madame Curie. By Tsai-Chien Chiang Translated by Tang-Fong Wong Of course, it may not be fair to compare two scientists half Aug 2012. (300pp.) a century apart, and with very different scientific knowledge 978-981-4374-84-2 (HC) US$98 and research environments. From the point of view of a 978-981-4368-92-6 (SC) US$48 Chinese, writing a biography of Wu Chien-Shiung and honestly recording the life of a recent world class Chinese scientist, is definitely an effort worth making. Wu Chien-Shiung was becoming world famous in the early 1950s after her works in nuclear physics. China was deep in civil war. In 1956, Wu was the first to perform a rather difficult and precise experiment, and confirmed the hypothesis proposed by C. N. Yang and T. D. Lee. Yang and Lee became the first two Chinese Nobel Laureates. Although Wu did not share the prize, to the surprise and a sense of un-fairness of many people, she was acknowledged as one of the most distinguished experimental physicists in the world. In 1962, Wu returned to Taiwan to attend the Congress of Academia Sinica and visited her teacher Hu Shi, but sadly witnessed the sudden death of her most beloved teacher. Wu returned again in 1965 to receive the Special Contribution Award from Chia Hsin Cultural Foundation. She presented public lectures in both visits, greatly contributed to sciences in Taiwan. Chinese biographies of scientists were usually written in As her research schedule became busier (she did not a naïve and shallow way, therefore not worth finishing. visit Taiwan since 1965), and the politics across the Taiwan This book however seriously and honestly presents the Strait exerted more negative impact on sciences, her eventual humanity and the backdrop of the success of Wu Chien- home coming to Mainland China in 1973 (after an absence Shiung. It opens a new era of such biographies. of 37 years) could not escape politics and criticism. In fact, C. N. Yang this home coming trip with both parents passing away since her venturing abroad, and a rapidly decreasing family, had already saddened her tremendously. Wu visited Taiwan upon the invitation of Academia Preface Sinica in 1983 after 18 years absence. I met her for the first t has been eight years since the first idea of writing this time as a science reporter of Reading Times, which served biography occurred to me. The actual starting of writing as the beginning of the adventure of writing this biography. was two years later. In this period, I have talked to many Wu, Chien-Shiung went to the US in 1936. By the time Ipeople about Wu Chien-Shiung: Some knew her a little, she earned a Ph.D. in 1940, her achievements and insights most had only vague understandings; some asked me why in research had already received the highest admirations of I should write a biography of Wu, and some even asked who many professors at UC Berkeley, such as the great American Wu Chien-Shiung was! scientists Oppenheimer and Lawrence. As a result, she was Who is Wu Chien-Shiung? Should we ever ask who is invited as a non-citizen to participate in the top-secret Madame Curie? Or people may ask: Shall we discuss Wu “Manhattan Project” working on atomic bombs, and made Chien-Shiung and Madame Curie in the same class? critical contribution to the project. Actually, people may know that Wu Chien-Shiung In a way, the participation in defense research was a

64 Asia Pacific Physics Newsletter BOOKS chanced opportunity. Wu Chien-Shiung had worked in What impressed me most was his assessment of an objec- nuclear physics research all her life. In this field, people tive narrative in these new publications. It is in contrast with all agree that she had made at least three major influential many Chinese biographies, which either glorify or demote achievements. In addition to the confirmation of the the characters, or use a novel like, subjective narrative. Mr. hypothesis put forth by Yang and Lee, the other two are Yang even recommended and accompanied me to buy a significant enough to be considered a Nobel Prize. In spite of newly published book discussing the scientists and the her outstanding scientific achievements, she was not as well surrounding events leading to the progress in physics in the known accordingly, perhaps because she never won a Nobel. late 20th Century. Although Wu Chien-Shiung never won a Nobel, she did In the exceptionally bright, sunny afternoon, I remem- receive numerous honors. The awards, medals, and honorary bered that Yang and I were waiting in the Stony Brook Train doctorates she received from institutes and universities Station (not even had a platform then), contemplating and form a long list, with the “Wolf Prize” endowed by an Israel searching for ideas. I then boarded the train back to New industrialist probably the most representative. One criterion York City. The new book recounts the sequence of events of the Wolf Prize is to honor candidates who deserve Noble leading to the discovery of the “J” particle by Samuel C. C. Prizes but do not get one. Therefore Wolf is known as the Ting. I was full of excitement and greatly moved beyond Israeli Nobel. Wu Chien-Shiung was indeed awarded the any description. first Wolf Prize in Physics in 1978. I discussed this proposal with Wu Chien-Shiung two In addition, she received the Cyrus B Comstock Award year afterwards. Wu was always matter-of-fact, modest, and (given once every 5 years) from the US National Academy of never seeking fame, and she declined once again. Only after Sciences, National Medal of Science, and the record breaking, many verbal and written persuasions, and the argument put first female honorary doctorate from Princeton University in forward by Luke Yuan that her biography will help inspiring 1958. In 1975, Wu broke the white-male-president tradition, Chinese youth in addition to publicizing her achievements, and became the first female President of American Physics was she finally convinced. Society. With the inspiration of Yang, I realized the very impor- Due to her significant achievements, and her profound tance of using an objective narrative in writing this book. As influences in physics, Wu Chien-Shiung was often called a result, I would not rely only on her own version, but would “The Chinese Madame Curie”, “The First Lady of Physics interview her colleagues, students, friends, relatives, and Research”, “Queen of Nuclear Research”, and “The Most even competitors, and make reference to many documents Distinguished Female Experimental Physicist in the World”. and literatures. This turned out to be a time-consuming Wu retired from Columbia University after 36 years in undertaking. 1980. As Professor Emeritus, her major research activities I started the official interviews with Wu Chien-Shiung in gradually slowed down. She was in her 70s, a good time for New York in September of 1989. They were un-expectedly reflection. My idea of writing this biography started then. rough. I had imagined a rather romantic setting, with Wu I received much encouragement when planning for this vividly recounting her life and events, while relaxing in biography, particularly from C. N. Yang, who had a special her chamber. With the tape recorder turning and my pen in-depth understanding of the scientific achievements of Wu moving, the sun would be setting slowly. But this almost Chien-Shiung, and had once a close collaboration with her. never happened in the tens of interviews in more than a year! Yang researched and taught in the US for many years, was Wu Chien-Shiung never wrote diary. While whole- well known for his nurturing and directing junior students, heartedly immersed in her scientific experiments in the especially the Chinese ones. I had such impression when past years, she never considered recording this process for I first visited him in New York in 1985. When I proposed the world, and therefore had no memory of many events. the plan writing this biography in 1987, Yang was greatly In addition, she was down-to-earth, and of few words. The interested, and warmly endorsed this effort. medicine lowering her blood pressure also affected her Yang mentioned that a distinguished scientist like Wu memory. The tens of hours of the interview and reminiscence Chien-Shiung deserves to have a good biography. A Chinese were not enough to reconstruct her past. author, with a different perspective, would better serve this In addition to the interviews, I have read more than 10 task. He suggested many ideas, and remarked about the relevant books, the personal archive of Wu Chien-Shiung exciting publications of many biographies of scientists in in Columbia University, historical documents in American recent years in the US. Physical Society, thousands of pages in newspapers,

September 2012, Volume 1 No 2 65 BOOKS magazines, and physics periodicals. Then there were the my newspaper work: one always feels that the materials were interviews with her relatives, friends, colleagues, students, incomplete, but has to put down words when facing dead scientific collaborators and competitors. I flew more than line. Similarly, there is a sense of lack of closure in the end, 30,000 miles all over the world to interview more than but one must do the best relying on whatever one can find 50 individuals in China, Hong Kong, Europe, US and from the recordings of her life events. Canada. The tape recording of tens of hours was followed There are always conflict and choice between pressure of by telephones calls to confirm details. time and completeness. I just hope that this book will meet Of course, the value of a book will be judged with many the expectation of concerned and helpful individuals. qualitative factors other than the above quantitative meas- ures. The above steps just illustrate how the writing of this Chiang Tsai-Chien book proceeded and developed. To establish the credibility of the material, I have used About the Author extensive end-of-chapter notes, references, and bibliogra- phies for critical sources, comments and conversations. I also Chiang Tsai-Chien. Born 1950. Graduated from Fu-Ren used objective narrative as much as possible, and avoided University in Mathematics. subjective opinion or novel style description. Basically, this Worked in sciences reporting and commentary for 18 book conforms to the current trend in biography writing, years in Reading Times, currently editor-in-chief. using a narrative style closer to news reporting. Had interviewed scientists, visited laboratories, and In a way, the writing of this book could be regarded as reported on important scientific activities in many countries an attempt to test the idea that “news serves as a footnote of in the world, reported on the Gulf War in Middle East in history”. There must be errors and omissions due to my own 1991. limited capacity, and I sincerely welcome your corrections. Greatly interested in science and news reporting, recently The completion of this task owes much to the contribu- devoted to the issues of impact and positioning of sciences tions and extraordinary help of many individuals, including on culture my relatives, colleagues, and many people, institutes, univer- sities in may countries that are referred to in this book. To Tang-Fong Wong. Earned a BS in Physics from Chinese avoid the embarrassment of possible omission, I decided not University of Hong Kong, and PhD. in Theoretical Physics to list their names, but sincerely express my utmost gratitude. from Brown University. Besides C. N. Yang who encouraged me to start this Taught and researched in Particle Physics at Brookhaven project at the very beginning, and gave me much direction National Labs and Rutgers University, and Management and assistance during the course, I received the most support Sciences at Bell Labs and AT&T. and assistance from Yu Ji-Zhong, CEO of the Reading Times where I worked. I remembered seeing Yu in the spring if 1989 to propose the project of writing this biography right after getting the approval from Wu Chien-Shiung. After some careful consideration, and probing questions, Yu imme- diately recognized the meaning and nature of this project, and granted me an un-precedent support of one-year leave from the daily grinding of newspaper reporting. I was able to stay in New York City where Wu Chien-Shiung lived for long-term interviews and collection of source materials, and I was able to travel several times to other locations in the US visiting relevant individuals. In the following years, the writing of the biography became irregular and with much delay, as I was involved in much reporting and planning back to the newspaper. Yu would always tell me not to hurry, as quality was a most important value. The experience of writing this biography was not unlike

66 Asia Pacific Physics Newsletter BOOKS

Introduction to Statistical hen students are first exposed at the undergrad- uate or graduate level to statistical mechanics, Mechanics they are still processing the tools and concepts of John Dirk Walecka (Stanford University) Wclassical mechanics, quantum mechanics, and electromagne- World Scientific, 2011. (365 pp.) tism. Thus it is important that a statistical mechanics course 978-981-4366-20-5 (HC) US$98 include expert teaching and guidance to relate that course’s 978-981-4366-21-2 (SC) US$58 concepts to students’ emerging interests. And students who eventually become researchers will find it helpful to have understand- able textbooks with which they can quickly reference important details for successful application of statistical mechanics. Two new statistical mechanics texts provide clarity on the subject’s key concepts and applications. Introduction to Statistical Mechanics by John Dirk Walecka makes the subject inviting and reads as a nice sequel to his Fundamen- tals of Statistical Mechanics: Manuscript and Notes of Felix Bloch (Stanford University Press, 1989; reviewed by Robert Pelcovits in PHYSICS TODAY, July 1990, page 69), which Walecka prepared and edited. Statistical Mechanics in a Nutshell by Luca Peliti is a more sophisticated presentation that will be of value to advanced students, lecturers, and practitioners. Walecka’s edited Bloch notes influenced my views on phase space, classical versus quantum pictures, and the density-matrix formalism. I recall Walecka writing in the Statistical Mechanics in a preface that he intended to use Bloch’s approach to teaching the subject, so I engaged Walecka’s Introduction to Statistical Nutshell Mechanics with an expectation of déjà vu. However, I found Luca Peliti (translated from Italian by Mark Epstein) the newer work to be an original and appealing presentation Princeton University Press, 2011. (398 pp.) 978-0-691-14529-7 (HC) US$75 and not a recast of Bloch’s notes. Overall, the text’s practical feel will give students a good sense of what it means to use statistical mechanics; that achievement is also shared by Ryōgo Kubo’s Statistical Mechanics: An Advanced Course with Problems and Solutions (2nd edition, North-Holland, 1988). Walecka provides a clear narrative with several standard calculations that students are often left alone to figure out on their own. One example concerns the method of steepest descent, an important technique used in several areas of physics. He also presents various applications of statistical ensembles, particularly in the section on molecular . In the classroom, applications tend to be limited to the problem sets, yet in this case students will gain from Walecka’s descriptive treatment of diatomic or polyatomic molecules in explaining molecular spectroscopy. Moreover, he also plants seeds for future learning in the chapter “Special topics,” which includes discussions of mean-field theory and order–disorder transitions. Promising though it is as introductory text, Introduction

September 2012, Volume 1 No 2 67 BOOKS to Statistical Mechanics contains some awkward notation. NEW BOOKS Instead of using the widely accepted β, Walecka writes out 1/ kBT. Also, I found it initially off-putting to see the partition ASTROPHYSICS AND COSMOLOGY function labeled as “p.f.”, though I came to appreciate that Astroparticle, Particle, Space Physics and Detectors for label more when I thought about how much effort it takes to Physics Applications-Proceedings of the 13th ICATPP write symbols for partition functions of different canonical Conference. Giani Simone. et. al. 2012. US$240 HC (1100pp.) ensembles. Such stylistic choices in notation and labeling ISBN 9789814405065 may bog down students, who should be focused on applying Beyond the Stars: Our Origins and the Search for Life in the tools of statistical mechanics to real, physical systems. the Universe. Saraceno Paolo. 2012. US$72 HC (388pp.) I believe Walecka’s notations were intended to dissuade ISBN 9789814295536 students from rote memorization and to focus them on a physical understanding of temperature and on building the correct partition function. OPTICS Peliti’s Statistical Mechanics in a Nutshell—originally Principles of Diffuse Light Propagation: Light Propaga- published in Italian (Bollati Boringhieri, 2003)—is a fantastic tion in Tissues with Application in Biology and Medicine. reference for those who know the subject, teach it, or need Ripoll Lorenzo Jorge. 2012. US$118 HC (356pp.) ISBN a quick technical reminder, especially on the topic of phase 9789814293761. transitions, which are consistently featured in modern-day Controlling Steady-State and Dynamical Properties of discussions and one that Walecka’s book omits. Browsing Atomic Optical Bistability. Joshi Amitabh. et. al. 2012. US$97 Peliti’s book reminded me of such texts as Kerson Huang’s HC (248pp.) ISBN 9789814307550 Statistical Mechanics (2nd edition, Wiley, 1987); David Chandler ’s Introduction to Modern Statistical Mechanics CONDENSED MATTER PHYSICS (Oxford University Press, 1987); and Mehran Kardar’s Correlated Electrons in Quantum Matter. Fulde Peter. of Particles and Statistical Physics of Fields 2012. US$168 HC (552pp.) ISBN 9789814390971 (both published by Cambridge University Press, 2007). Optoisolation Circuits: Nonlinearity Applications in Of the books under review, Statistical Mechanics in a Engineering. Aluf Ofer. 2012. US$164 HC (664pp.) ISBN Nutshell provides the more general overview, with topics 9789814317004 such as the renormalization group method. It includes a good mix of fundamental thermodynamics, phase behavior, and other key subjects. Even so, I do not see it as a standalone HIGH ENERGY PHYSICS book for introductory students, even if they are energetic and Silicon Solid State Devices and Radiation Detection. serious; they will need an expert teacher or practitioner to Leroy Claude. et. al. 2012. US$135 HC (432pp.) ISBN make the ideas become more vivid in the classroom. 9789814390040 ABC of Physics: A very Brief Guide. Okun Lev Borisovich. Reviewed by Kimani A. Stancil 2012. US$28 HC (168pp.) ISBN 9789814397278 (Howard University Washington, USA)

Reprinted with permission from Physics Today 65 (8), 50 (2012). Copyright PLASMA PHYSICS 2012, American Institute of Physics. Basic Space Plasma Physics (Revised Edition). Baumjohann. 2012. US$128 HC (496pp.) ISBN 9781848168947 QUANTUM PHYSICS Introduction to Quantum Mechanics: Schrodinger Equa- tion and Path Integral (Second Edition). Muller-Kirsten. 2012. US$158 HC (944pp.) ISBN 9789814397735 Quantum Computing from the Ground up. Perry Riley Tipton. 2012. US$49 SC (256pp.) ISBN 9789814412117

68 Asia Pacific Physics Newsletter RESEARCH INSTITUTES AND LABS IUCAA Inter-University Centre for Astronomy and Astrophysics, Pune, India A Brief Description

Ajit Kembhavi Director, IUCAA, Pune, India

he Inter-University Centre for Astronomy and Astro- physics (IUCAA), located in the city of Pune in India, is an autonomous institution under the University TGrants Commission (UGC). It is a centre of excellence for research in astronomy and astrophysics (A&A) and related areas. It also serves as a platform for the entire university community in the country for work in A&A. IUCAA has a vibrant environment for research and development and attracts hundreds of national and international visitors every year who use its facilities, benefit from the interaction with the faculty and provide their own expertise to the centre. Research: IUCAA has distinguished faculty of 16 members at present, about 20 postdoctoral fellows and about 30 research students. In addition, a number of research IUCAA has an excellent computing environment students registered in various universities in India and including some of the best High Performance Computing abroad spend long period of time at IUCAA, thus widening (HPC) facilities in the country. The National Virtual the pool of young persons available for implementing various Observatory project is located at IUCAA. It brings together programmes. The research carried out has a broad range expertise from research institutions and the thriving software including theoretical astrophysics and cosmology, relativity industry in India to develop products and services, under the and gravitational theory, observational astronomy in optical umbrella of the International Virtual Observatory Alliance near-infrared radio and X-ray bands, and the development of (IVOA), for enabling and facilitating the use of vast quanti- an advanced astronomical instrumentation. IUCAA faculty ties of astronomical data which are becoming available from and students produce a large number of research papers various astronomical surveys. every year which are published in high impact international The instrumentation laboratory at IUCAA has been very journals. productively engaged in developing advanced astronomical Facilities: IUCAA has its own two-metre optical and instrumentation and is engaged in various national and near infrared telescope located at Giravali which is about international collaborations. Over the past few years it has 100 km away from the campus in Pune. IUCAA also has developed controllers for detectors on spectrographs on a share, as a member of an international consortium, in SALT and other telescopes, an adaptive optics system in the 11-metre Southern African Large Telescope (SALT). In collaboration with the California Institute of Technology addition, observers from IUCAA regularly obtain time on for use on small and medium class optical telescopes, and is international facilities on the ground and in space through developing a multi-fibre spectrograph for the new 3.6-metre competitive proposals. telescope belonging to ARIES, Nainital.

September 2012, Volume 1 No 2 69 RESEARCH INSTITUTES AND LABS

IUCAA is an important contributor to the development of various instruments on ASTROSAT, which is a multi- wavelength astronomical satellite to be launched by the Indian Space Research Organization (ISRO) in 2013, and is also contributing substantially to the software related to the mission. Two major proposals which have been made by Indian astronomers to the Government of India are participation in the Thirty Metre Telescope (TMT) project and the building of LIGO detector for gravitational waves on a suitable site in the country. India is expected to be an important partner in these projects and IUCAA will be one of the principal investigating institutions for both the projects. Visitors Programme: As an inter-university centre, up six IUCAA Resource Centres (IRCs) and several Nodes IUCAA has developed an extensive visitors programme. It facilitating for the development of A&A in remote locations. has on its roll about a hundred Visiting Associates from the All these programmes have led to a significant increase universities and colleges in India. Each associate spends a in research and development in A&A in the country. An month or more at IUCAA every year to use the facilities, extensive summer programme including lectures, hands-on interact with the faculty and other visitors and to carry out training and projects is carried out at IUCAA for students research and various developmental activities. University at various levels. research students, including students of associates, can spend Public Outreach: IUCAA has a very well developed and several months every year at IUCAA. For all such visits funded Public Outreach Programme. This is carried out at IUCAA provides funds for travel and stay and allows full the school level, early college level as well as for the general access to all its facilities including computers and telescopes. public. A special Science Centre and Science Park have been The IUCAA guest house can accommodate about a hundred developed in the campus for visitors and students. Lectures visitors at a given time. Faculty and students from other and demonstrations on astronomy as well as other areas of countries are also regular visitors. science are regularly organized and special events like the IUCAA conducts a number of training and research National Science Day on February 28 which are celebrated workshops every year on its campus as well as on various every year attract many thousands of visitors. university and college campuses in the country. It has set iucaa.ernet.in 70 Asia Pacific Physics Newsletter RESEARCH INSTITUTES AND LABS Institute for Advanced Study Hong Kong University of Science and Technology A Brief Status Report

he Institute was founded in 2006 by Paul Chu as At the same time, IAS continues its successful program the founding director. Since January 2011, Henry of bringing distinguished speakers (about 60 every year) to Tye from Cornell University has been its director. campus to deliver lectures that appeal to a broad audience. TInstead of modeling after Princeton IAS, the Institute is now We further strengthen the program of bringing visiting closer in spirit and structure to KITP in UCSB and Hoover professors and fellows (see Appendix 2) to campus for Institution at Stanford, as an integral part of the university, extended periods to interact as well as collaborate with yet with its own identity and recognition. Recruitment of IAS HKUST faculty and students. When the new building is professors is actively underway. Each IAS professor will hold ready, we plan to start seminar series in a dozen or so topics a joint appointment with a department in HKUST. We are open for all scholars in Hong Kong. In addition, to engage optimistic to have the first appointments on board in 2013 all academics in Hong Kong and worldwide, we organize when the new IAS building will be completed for moving in. programs similar in format to those at KITP but include all To bring IAS closer to the university proper, 15 of the areas in theoretical science. Office space will be provided most prominent and active professors who are presently not for all those coming to IAS for events or communications. senior administrators (associate deans and department heads and above) have been appointed as IAS Senior Fellows (see Activities Appendix 1). They will liaise with the rest of the University as well as provide a vibrant intellectual atmosphere at IAS. Some 236 events (distinguished lectures, seminars, forums, confer- of them will also lead new initiatives in inter-disciplinary ences, workshops, etc.) were organized from June 2006 to areas of research. date, with close to 60 each in 2010 and 2011.

Research programs • Cosmology and String Theory (3 Jan – 31 Aug 2011) • Arithmetic Geometry and Representation Theory (15 Dec 2011 – 15 Jan 2012) • Metamaterials, Plasmonics & Transformation Optics (8 Oct – 30 Nov 2012) • Topological Materials and Strongly Correlated Electronic Systems (3 Dec 2012 – 31 Jan 2013)

Gordon Research Conferences One of the two site partners in Hong Kong to host the new

IAS’s new office, Lo Ka Chung Building (盧家驄薈萃樓) is still under “GRCs in Asia”, four are planned for summer 2013 and more construction and targeted for completion by 2012 Q4. in 2014 and beyond.

September 2012, Volume 1 No 2 71 RESEARCH INSTITUTES AND LABS

Appendix 1 Appendix 2 IAS Senior Fellows IAS Visiting Professors (arranged by Schools and Departments/Divisions) • Robert Austin, Professor of Physics, Princeton University Name Department / Division (NAS)

School of Science • Aaron Ciechanover, Distinguished Research Professor, ZHANG, Mingjie Life Science Rappaport Faculty of Medicine and Research Institute, TANG, Ben Zhong Chemistry Technion - Israel Institute of Technology (2004 Nobel LI, Jian-Shu Mathematics Prize in Chemistry; NAS; AAAS) SHENG, Ping Physics • Marvin Cohen, Professor of the Graduate School, Depart- SHIU, Gary (1) Physics ment of Physics, University of California, Berkeley (2001 US National Medal of Science; NAS; AAAS) School of Engineering NG, Charles Civil & Environmental • Steven DenBaars, Professor of Materials and Electrical Engineering & Computer Engineering, University of California, Santa KWOK, Hoi Sing Electronic & Computer Barbara (NAE) Engineering LEE, Chung-Yee Industrial Engineering & • Richard C. Flagan, Irma and Ross McCollum-William Logistics Management H. Corcoran Professor of Chemical Engineering and ZHANG, Tongyi Mechanical Engineering Professor of Environmental Science & Engineering, California Institute of Technology (NAE) (incoming) School of Business & Management CHEN, Songnian Economics • Roland Glowinski, Cullen Professor of Mathematics and Mechanical Engineering, University of Houston DASGUPTA, Sudipto Finance (Academia Europaea) HA, Albert Information Systems, Business Statistics & Operations • Chih-Ming Ho, Ben Rich-Lockheed Martin Chair Management Professor, School of Engineering, University of California, Los Angeles (NAE; Academia Sinica) School of Humanities & Social Science LI, Bozhong Humanities • Thomas Y. Hou, Charles Lee Powell Professor of Applied KUNG, James Social Science and Computational Mathematics, California Institute of PARK, Albert (2) Social Science Technology (AAAS)

(1) Incoming • Roger E. Howe, William R. Kenan Jr. Professor of Math- (2) Concurrently Professor of Economics ematics, Yale University (NAS; AAAS)

• Thomas K. Kuech, Milton J. and A. Maude Shoemaker Professor, Chemical and Biological Engineering Depart- ment, University of Wisconsin-Madison (NAE)

• Hau L. Lee, Thoma Professor of Operations, Information and Technology, Stanford University (NAE)

• Patrick A. Lee, William & Emma Rogers Professor of Physics, Massachusetts Institute of Technology (2005 Dirac Medal & Prize (ICTP); NAS)

72 Asia Pacific Physics Newsletter RESEARCH INSTITUTES AND LABS

• Steven G. Louie, Professor of Physics, University of • Bing Xu, Vice-President, China Central Academy of Fine California, Berkeley (NAS; AAAS; Academia Sinica) Arts

• Eric Maskin, Professor of Economics, Harvard University • Eli Yablonovitch, James & Katherine Lau Chair in Engi- (2007 Nobel Prize in Economics) neering, Electrical Engineering and Computer Science, University of California, Berkeley (NAE; NAS) • Shuji Nakamura, Professor of Materials, University of California, Santa Barbara (2006 Millennium Technology • Shou-Wu Zhang, Professor of Mathematics, Princeton Prize; NAE) University and Professor of Mathematics, Columbia University (AAAS) • Stanley Osher, Professor of Mathematics, University of California, Los Angeles (NAS; AAAS) • Ya Qin Zhang, Corporate Vice President, Microsoft Corporation • George Papanicolaou, Robert Grimmett Professor in Mathematics, Stanford University (NAS; AAAS) IAS Senior Visiting Fellows • Antony Galione, Statutory Professor of Pharmacology, • John Pendry, Chair Professor in Theoretical Solid State University of Oxford Physics, Imperial College London (1996 Dirac Medal & Prize (IOP); FRS; Knight Bachelor) • Jason Ho, Distinguished Professor of Mathematical and Physical Sciences, Ohio State University • Paul Schimmel, Ernest and Jean Hahn Professor, Skaggs Institute for Chemical Biology, The Scripps Research • Bei-Lok Bernard Hu, Professor of Physics, University of Institute (NAS; AAAS) Maryland

• Surendra P. Shah, Walter P. Murphy Professor, Depart- IAS Affiliate Members ment of Civil & Environmental Engineering, North- • Xiren Cao, Professor Emeritus, Department of Electronic western University (NAE; CAE) and Computer Engineering, The Hong Kong University of Science and Technology • Yuen-Ron Shen, Professor of the Graduate School, Professor Emeritus, Department of Physics, University • Michael Loy, Chair Professor, Department of Physics, of California at Berkeley (NAS; AAAS; Academia Sinica) The Hong Kong University of Science and Technology

• Bright Sheng, Leonard Bernstein Distinguished Univer- • Xiang-Lei Yang, Associate Professor, Department of sity Professor of Music, University of Michigan Chemical Physiology, The Scripps Research Institute

• Ching W. Tang, Doris Johns Cherry Professor of Chemical ias.ust.hk Engineering, University of Rochester (2011 ; NAE)

• Pravin Varaiya, Professor of the Graduate School, Elec- trical Engineering and Computer Science, University of California, Berkeley (NAE; AAAS)

• Jeff Wu, Coca-Cola Chair in Engineering Statistics and Professor, School of Industrial and Systems Engineering, Georgia Institute of Technology (NAE; Academia Sinica) (incoming)

September 2012, Volume 1 No 2 73 CONFERENCE CALENDAR Upcoming Conferences in the Asia Pacific Region

SEPTEMBER 2012 10 – 14 Sep 2012 24 – 28 Sep 2012 HPLS&A2012 — The XIX International Symposium RuPAC 2012 — XXIII Russian Particle Accelerator 2 – 7 Sep 2012 on High Power Laser Systems & Applications, Conference 12th International Conference on Radiation Istanbul 2012 Saint-Petersburg, Russia Shielding ICRS12 and 17th Topical Meeting of the Istanbul, Turkey http://www.apmath.spbu.ru/rupac2012/ Radiation Protection and Shielding Division of the http://hplsa2012.mam.gov.tr/ American Nuclear Society RPSD2012 27 – 29 Sep 2012 Nara, Japan 10 – 14 Sep 2012 NSRP 19 — 19th National Symposium on Radiation http://www.icrs12.org/main/ 2nd Annual Conference on Quantum Cryptography Physics (QCRYPT 2012) Chennai, India 2 – 7 Sep 2012 Shaw Foundation Alumni House, NUS, Singapore http://www.nsrp19.com 18th International Conference on Ion Beam http://www.qcrypt.net/ Modifications of Materials (IBMM2012) Qingdao, China 16 – 22 Sep 2012 OCTOBER 2012 http://www.ibmm2012.org 2nd Particle Physics School in South-East Asia 1 – 6 Oct 2012 Yogyakarta, Indonesia NEPCAP 2012 — 5th International Symposium on 3 – 28 Sep 2012 http://ppssea.kek.jp/2012/ Non-equilibrium Processes, Plasma, Combustion, Cosmology and Astroparticle Physics and Atmospheric Phenomena KITPC, Beijing, China 17 – 22 Sep 2012 Sochi (Loo), Russia http://kitpc.itp.ac.cn Metamaterials 2012: The 6th International http://www.nepcap2012.ciam.ru/ Congress on Advanced Electromagnetic Materials in 5 – 6 Sep 2012 Microwaves and Optics 1 – 6 Oct 2012 Asia-Pacific Econophysics Conference 2012 St. Petersburg, Russia EXON-2012 — VI Traditional International Taipei, Taiwan http://congress2012.metamorphose-vi.org/ Symposium on Exotic Nuclei http://conference.nccu.edu.tw/actnews/content. Vladivostok, Russia php?Sn=28 17 – 22 Sep 2012 http://exon2012.jinr.ru/ 20th International Symposium on Spin Physics 6 – 8 Sep 2012 (SPIN2012) 2 – 4 Oct 2012 International Conference on Flexible and Printed JINR, Dubna, Russia Workshop on QCD in two-photon process Electronics http://theor.jinr.ru/spin2012/ Academia Sinica, Taipei, Taiwan Tokyo, Japan http://www.icfpe.jp 23 – 28 Sep 2012 http://belle.kek.jp/~nkzw/tpqcd12.html 17th International Conference on Molecular Bean 10 – 13 Sep 2012 Epitaxy (MBE2012) 5 – 7 Oct 2012 Workshop on the Magellanic Clouds Nara, Japan International Conference on Nanostructures, Perth, Australia http://mbe2012.jp Nanomaterials and http://www.icrar.org/news/magellanic-clouds- Nanoengineering -ICNNN 2012 workshop 23 – 28 Sep 2012 Singapore Institute of Electronics (SIE), Singapore The 37th International Conference on Infrared, http://www.icnnn.org/ 10 – 13 Sep 2012 Milimeter, and Terahertz Waves (IRMMW-THz) IAEA-NFRI — Joint IAEA-NFRI Technical Meeting on Wollongong, NSW, Australia 14 – 18 Oct 2012 Data Evaluation for Atomic, Molecular and Plasma- http://irmmwthz2012.uow.edu.au Conference on Computational Physics 2012 Material Interaction Processes in Fusion (CCP2012) Daejeon, South Korea 23 – 28 Sep 2012 Kobe, Japan http://www-amdis.iaea.org/meetings/NFRI2012/ International Union of Materials Research Societies http://www.ile.osaka-u.ac.jp/CCP2012/ International Conference 10 – 14 Sep 2012 on Electronic Materials 2012 (IUMRS-ICEM 2012) 14 – 18 Oct 2012 8th International Workshop on Microwave Pacifico Yokohama, Yokohama, Japan Horizons of Quantum Physics — Horizons of Discharges: Fundamentals and Applications http://iumrs-icem2012.org/index.html Quantum Physics: from Foundations to Quantum- Zvenigorod, Russia Enabled Technologies http://www.fpl.gpi.ru/md-8/index.html Taipei City, Taiwan http://www.quantumhorizons.org

74 Asia Pacific Physics Newsletter CONFERENCE CALENDAR

15 – 19 Oct 2012 22 – 25 Oct 2012 7 – 10 Nov 2012 The 6th International Conference on Multiscale International Conference on Emerging Advanced iCAST2012 — International Conference on Materials Modeling (MMM 2012) Nanomaterials Advancement in Science and Technology 2012, http://www.mrs.org.sg/mmm2012 Brisbane, Australia Contemporary math., Math. Phys, and appl. http://www.uq.edu.au/iceanconference Kuantan, Malaysia 15 – 19 Oct 2012 http://iium.edu.my/icast/2012/ OFS-22 — 22nd International Conference on 22 – 26 Oct 2012 Optical Fiber Sensors Physics of Light Exotic Nuclei ( EURISOL week ) 12 – 14 Nov 2012 Beijing, China Hayama (Kanagawa), Japan A-SSCC — 2012 IEEE Asian Solid-State Circuits http://www.ofs-22.org http://www.eurisol.org/usergroup/?p=209 Conference Kobe, Japan 15 – 19 Oct 2012 22 – 26 Oct 2012 http://www.a-sscc2012.org/ MMM 2012 — Multiscale materials modeling ISAPE - 2012 — 2012 10th International Biopolis, Singapore Symposium on Antennas, Propagation & EM Theory 12 – 16 Nov 2012 http://www.mrs.org.sg/mmm2012 Xi'an, China RESCEU Symposium on General Relativity and http://www.isape.org/ Gravitation 16 – 18 Oct 2012 Tokyo, Japan BMEI — 2012 5th International Conference on 23 – 30 Oct 2012 http://www.resceu.s.u-tokyo.ac.jp/symposium/ Biomedical Engineering and Informatics 10th Asia International Seminar on Atomic and jgrg22/ Chongqing, China Molecular Physics (AISAMP10) http://cisp-bmei.cqupt.edu.cn http://www.aisamp10.tw 12 – 16 Nov 2012 Eclipse on the Coral Sea 16 – 19 Oct 2012 27 – 29 Oct 2012 Queensland, Australia SPERA2012 — 12th South Pacific Environmental T&SA — 2012 IEEE Conference on Technology and http://moca.monash.edu/eclipse Radioactivity Association Bi-annual Conference Society in Asia Sydney, Australia Singapore 13 – 15 Nov 2012 http://www.ainse.edu.au/events2/conferences/ http://www.TechnologyandSocietyinAsia.org/ IPIN — 2012 International Conference on Indoor spera_2012 Positioning and Indoor Navigation 28 – 31 Oct 2012 Sydney, Australia 18 – 21 Oct 2012 2012 IEEE Sensors http://www.surveying.unsw.edu.au/ipin2012/ International Conference on High Energy Density Taipei, Taiwan home.php Physics http://www.ieee-sensors2012.org Peking University, China 16 Nov 2012 http://capt.pku.edu.cn/ichedp.html 30 Oct – 2 Nov 2012 SPERA2012 — 12th South Pacific Environmental 25th International Microprocesses and Radioactivity Association Bi-annual Conference 19 – 21 Oct 2012 Nanotechnology Conference (MNC 2012) Sydney, Australia ICCP — 2012 International Conference on Kobe, Japan http://www.ainse.edu.au/events2/conferences/ Computational Problem-Solving http://imnc.jp spera_2012 Leshan, China http://www.ic-cp.org/2012 18 – 23 Nov 2012 NOVEMBER 2012 XV International Conference on Small-Angle 21 – 25 Oct 2012 Scattering SAS 2012 5 – 9 Nov 2012 25th International Conference on Atomic Collisions Sydney, Australia 1st Southeast Asian Young Astronomers in Solids http://www.sas2012.com/ Collaboration (SEAYAC) Meeting Kyoto, Japan Puerto Princesa City, http://icacs25.riken.jp/ 19 – 21 Nov 2012 The Epoch of Reionisation global signal: theory, 6 – 9 Nov 2012 21 – 26 Oct 2012 experiments and outlook CEEM 2012 — 2012 6th Asia-Pacific Conference on 16th International Conference on Electromagnetic Sydney, Australia Environmental Electromagnetics Isotope Separators and Techniques Related to their http://caastro.org/event/eor-global-signal- Shanghai, China Applications (EMIS2012) workshop http://www.emc2012beijing.com Kanto, Japan http://indico.riken.jp/indico 19 – 21 Nov 2012 6 – 9 Nov 2012 2012 National Conference on Physics - PERFIK Axion Cosmophysics Pahang, Malaysia KEK, Japan http://www.ukm.my/perfik2012 http://www-conf.kek.jp/AIU12

September 2012, Volume 1 No 2 75 CONFERENCE CALENDAR

19 – 21 Nov 2012 8 – 10 Dec 2012 12 – 22 Mar 2013 ICRTNP-2012 — International Conference on IMCCC — 2012 Second International Conference EDIT 2013 Recent Trends in Nuclear Physics-2012 on Instrumentation, Measurement, Computer, Excellence in Detectors and Instrumentation Solan, India Communication and Control Technologies http://www.chitkara.edu.in/pdf/ICRTNP_2012.pdf Harbin City, Heilongjiang, China KEK, Japan http://imccc2012.hit.edu.cn http://edit2013.kek.jp 19 – 22 Nov 2012 APCTP Workshop on Astrophysics: Magnetic Fields 9 – 13 Dec 2012 18 – 22 Mar 2013 in Astrophysics MSEAEA Workshop — 68th IUVSTA WORKSHOP International Workshop on Determination of the Pohang, South Korea "Multifunctional Surface Engineering for Advanced Fundamental Parameters of QCD http://www.apctp.org/plan.php/kj2012 Energy Applications" Institute of Advanced Studies, Nanyang Hong Kong, China Technological University, Singapore 21 – 24 Nov 2012 http://www.cityu.edu.hk/cosdaf/MSEAEA2012/ http://www.ntu.edu.sg/ias ICHDMS-2012 — Internaltional Conference on Index.html History and Development of Mathematical Sciences Rohtak, India 9 – 13 Dec 2012 MAY 2013 http://www.mdurohtak.ac.in/international_ 20th Australian Institute of Physics Congress 6 – 9 May 2013 conference/ Sydney, Australia International Conference on the Use of Computers http://www.aip2012.org.au/ in Radiation Therapy (ICCR 2013) 26 – 29 Nov 2012 Melbourne, Australia 7 th International Conference on Photonics and 9 – 14 Dec 2012 http://iccr2013.org Applications (ICPA-7) The 8th Asian Meeting on Ferroelectrics (AMF-8) Ho Chi Minh City, Vietnam Pattaya, Thailand 13 – 17 May 2013 http://www.iop.vast.ac.vn/activities/HNQHQP_ http://www.slri.or.th/amf8/ ICPA/07/ IPAC13 — 2013 International Particle Accelerator Conference 15 – 19 Dec 2012 Shanghai, China MMM 2012 — Multiscale materials modeling http://www.aps.org/meetings/meeting. DECEMBER 2012 Biopolis, Singapore cfm?name=IPAC13 http://www.mrs.org.sg/mmm2012 3 – 7 Dec 2012 Asia-Pacific Conference & Workshop in Science JULY 2013 Putrajaya, Malaysia JANUARY 2013 14 – 19 Jul 2013 http://einspem.upm.edu.my/6APCWQIS 7 – 11 Jan 12th Asia Pacific Physics Conference IAU Symposium 296: Supernova Environmental 3rd Asia-Europe Physics Summit (ASEPS) 3 – 28 Dec 2012 Impacts Chiba, Japan Molecular Junctions Raichak near Kolkata, India http://www.jps.or.jp/APPC12 KITPC, Beijing, China http://www.iau.org/science/meetings/future/ http://kitpc.itp.ac.cn symposia/1061/ 15 – 19 Jul 2013 Reionization in the Red Centre: New Windows on 4 – 6 Dec 2012 27 Jan – 8 Feb 2013 the High Redshift Universe Nishinomiya Yukawa Symposium: New Waves in School on Low Dimensional System Ayers Rock Resort, Uluru-Kata Tjuta National Park, Gravity and Cosmology Institute of Advanced Studies, Nanyang Australia Yukawa Institute for Theoretical Physics Technological University, Singapore http://www.caastro.org/event/caastro-annual- Kyoto, Japan http://www.ntu.edu.sg/ias science-conference http://www2.yukawa.kyoto-u.ac.jp/ws/2012/ gc2012/symposium/ 24 – 31 Jul 2013 MARCH 2013 XXVIII ICPEAC — XXVIII International Conference 5 – 7 Dec 2012 On Photonic, Electronic and Atomic Collision PA 2012 — 11th Asia-Pacific Conference on 4 – 8 Mar 2013 Institute of Modern Physics, Chinese Academy of Engineering Plasticity and Its Applications 2nd Complexity Conference Sciences Singapore, Singapore Institute of Advanced Studies, NTU, Singapore Lanzhou, China http://www.aepa2012.org/ http://www.ntu.edu.sg/ias http://210.77.72.2/usr/yzwl1/icpeac/ICPEAC2013. htm APPN CONFERENCE CALENDAR welcomes conference information in the Asia Pacific Region. To submit, send e-mail to [email protected]

76 Asia Pacific Physics Newsletter JOBS

Frontier Institute of Science and Current areas of research focus of interest to physicists include: Technology (FIST), Xi’an Jiaotong • experimental and theoretical condensed matter physics University (XJTU) • quantum theory and applications in computing and optics • nanomaterials and photovoltaic materials Seven Center Directorships, multiple vacancies for open-rank • structural ultramicroscopy and tomography tenure-track faculty, and postdoctoral research fellows (Valid through December 31, 2012) • mathematical and physical biology • information in biological systems FIST is a large selective investment by XJTU in an effort to establish a world-class, multi-disciplinary research institute. To achieve this goal, FIST • imaging and instrumentation is setting up 14 research centers of excellence in Mathematics, Physics, • catalysis and protein engineering marine and oceanography Chemistry, Bio-Science/Life-Science/ Basic-medical-Science, and Materials Visit www.oist.jp or write to [email protected] for information on how to apply. Science, and adopts a new management system similar to that of most U.S. Job benefits: Healthcare + Benefits package + Housing costs universities. Seven out of the 14 planned centers have been established recently, and FIST is now recruiting the remaining seven Center Directors (either full-time or honorary). In addition, FIST invites applications to fill its multiple, full-time tenure-track faculty positions at all levels (from lab director to group leader), as well as postdoctoral positions. See our Chinese ad at UNIVERSITY OF TSUKUBA, JAPAN http://fist.xjtu.edu.cn/zp.php?id=5 for details. Position: Associate Professor An eligible candidate for the Center Director position should be an Faculty: College of Engineering Sciences internationally renowned scientist and established leader in his/her field, Application Deadline: 19 October 2012 with the ability and will to build his/her center into an internationally (must arrive in the post by this day) recognized center of excellence. Successful candidates will be provided with Area of Expertise a sizable start-up package to establish a research center, together with a • Condensed matter and/or materials research in a broad sense including salary (500k-800k RMB annually for full-time directors) or an honorarium soft matter research, either theoretical or experimental. commensurate with the working days (for honorary directors). See our Chinese ad at http://fist.xjtu.edu.cn/zp.php?id=5 for details. • English education and science & engineering education in English at the College of Engineering Sciences, the Graduate School of Pure and In addition to the Center Director positions, FIST also invites applications in Applied Sciences and through campuswide programs. the above-mentioned areas to fill its full-time, tenure-track faculty positions at all levels, from lab director to group leader. Applications for postdoctoral Qualifications positions are also welcome. An eligible faculty candidate should have a track- • The candidate must have a doctorate degree. record for excellence in research and the potential to lead a lab or a group • English must be the candidate's first language. to success. Successful candidates will be provided with a competitive start- 2 up package including an annual salary of 100k-500k RMB, 15-200m lab Documents to be Submitted space, and enough start-up fund, together with many other benefits. Position • Curriculum vitae( download the form from http://www.oyoriko.tsukuba. level and start-up package will vary with the candidate’s qualification. See ac.jp/CVF1.doc ) our Chinese ad at http://fist.xjtu.edu.cn/zp.php?id=5 for details. • A list of publications (original articles, review articles and books) Interested individuals should set up their free ResearcherID webpage on • A copy each of five most significant publications (reprints or http://www.researcherid.com/. Please send your ResearcherID citation photocopies) information along with a cover letter, CV, and a list of 10 representative publications to Dr. Xiangli Meng, Frontier Institute of Science and Technology • An essay on your aspirations with regard to English education for (FIST), Xi’an Jiaotong University, 1 West building, 99 Yanxiang Road, Yanta undergraduate and postgraduate students of science and engineering District, Xi’an, Shaanxi Province, P.R.China, 710054. Tel./Fax: +86 29 (one A4 page) 83395131, email: [email protected]. XJTU is an AA / EOE employer. • A summary of your research till present and your future research plans (two A4 pages) • The names and addresses of two persons who can be contacted for comments The Okinawa Institute of Science and • Your affiliation, address, phone number, email address, and the name Technology Graduate University, and address of a contact person in Japan if there is one Japan Submission of Application PhD Programs in Physics in Japan (English) Please indicate "Faculty Position Application" in RED on the envelope Our program is based on a firm foundation in the basic sciences and our and post it by registered mail to: Nobuyuki Sano, Dean of the College of non-departmental structure encourages interactions across traditional Engineering Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8573, disciplinary boundaries. We are searching internationally for students Japan who will flourish in an atmosphere of encouragement for discovery and innovation. The OIST PhD program is flexible, individualised, and well- For further information, please contact T.Takemori resourced, offering top-notch facilities and close supervision in a supportive Tel: +81-298-53-5312, community environment. All students receive an internationally competitive Email: [email protected] support package. http://www.oyoriko.tsukuba.ac.jp/english/

September 2012, Volume 1 No 2 77 JOBS

SAHA INSTITUTE OF NUCLEAR PHYSICS, largest in the Asia-Pacific. With its headquarters in Singapore and offices in New Jersey, London, Hong Kong, Taipei, Beijing, Shanghai and Chennai, it INDIA now publishes about 500 titles a year and 120 journals in various fields. The Faculty Positions Company is searching for talented, innovative and result oriented individual SINP invites applications for faculty positions at different levels from to join our dynamic team in our Headquarter in Singapore: scientists having outstanding academic records and research achievements. Position At present major research activities of the Institute are in the following Editor responsible for publications in Physics, Mathematics, Materials broad areas : Atomic, Nuclear and Plasma Physics, Condensed Matter & Science and Engineering Surface Physics, High Energy Physics, Theoretical & Mathematical Physics and Biophysical Sciences. SINP is an autonomous organization funded by Responsibilities the Department of Atomic Energy of Government of India to carry out basic Responsible for the editorial process, from manuscript to publication: research in the above broad areas. SINP has excellent state-of-the-art in- • To build author, editor, reviewer network among scientific community house facilities and also has collaborative access to various high energy • To keep abreast of the latest development of responsible subject areas, accelerators and synchotron facilities across the world. focus on emerging or hot topics as well as interdisciplinary research. We seek applicants, who will complement and extend our current research • To plan, acquire and manage Editorial Projects, including journals, activities. Prospective applicants should also have interest in graduate books, proceedings and electronic products in Physics, Mathematics and teaching. This is a rolling advertisement (refer http://ww.saha.ac.in/cs/ www/position/Selection_Procedure.pdf) and applications may be submitted Requirements: anytime of the year in plain papers/e-mails with details like cover letter, • Bachelors/Masters/PhD degree in Physics or related disciplines, with at resume giving entire list of publications, a statement of research plan and least 2 years of relevant publishing experience contact details of 5 references. Salary and rank will be commensurate with qualifications and research experience – minimum of 2 years of postdoctoral • Strong interest in networking with authors, academic professionals or experience is required. researchers • Must have initiative, creativity and a keen eye for detail Director, Saha institute of Nuclear Physics, 1/AF,Bidhannagar, Kolkata 700064, INDIA; [email protected] • Experience in journalism and/or academic publishing preferred • Must be academically oriented with excellent command of English For more information and to apply online visit www.saha.ac.in • Strong organizational skills, detail oriented, and capable to handle multiple priorities. • Experience in identifying and recruiting potential authors NATIONAL TAIWAN UNIVERSITY, TAIWAN • Strong interpersonal and communication (written and verbal) skills Faculty Positions in Physics, Applied physics and Astrophysics The Department of Physics, the Graduate Institute of Applied Physics and the Potential candidates who meet our requirements may apply with a cover Graduate Institute of Astrophysics of National Taiwan University seek to fill letter and full resume in both English stating your current and expected several faculty positions, effective August 2013, at the Assistant, Associate or salaries, availability and contact details to [email protected] Full Professor level commensurate with qualifications. Serious consideration will be given to outstanding candidates in all fields of physics. Candidates Only shortlisted candidates will be notified. should be able to teach effectively at both graduate and undergraduate levels, and conduct a vigorous research program at the same time. Postdoctoral or faculty experience is highly desirable.

Applicants should submit a CV with publication list, a statement of research NATIONAL INSTITUTE FOR MATERIALS interests, and arrange to have at least 3 letters of reference sent to: SCIENCE (NIMS), JAPAN Professor Yee Bob Hsiung, Chairman, Department of Physics, National Taiwan University, Taipei, Taiwan, 10617 (Fax: +886-2-2363-9984, Email: yunting@ Permanent Resarcher - Nanoscale Materials Division phys.ntu.edu.tw). A successful candidate is required to perform outstanding theoretical study on condensed matter physics and related materials science, with focus Please make sure all the materials arrive at the Department before Oct. 12, on superconductivity, topological orders and materials, spintronics, and 2012. Application review will begin on Oct. 15, 2012, until all positions are related electronic properties and systems. The main target will be strong filled. correlation effects approached in terms of analytic and numeric techniques. Contributions to bridging fundamental physics concepts and functional materials and nano systems are requested. Requirement World Scientific Publishing Company Candidates should have a Ph.D. degree or expect to receive the degree by the start of employment. Young scientists, who have rich experiences in In search of … Great Minds one or more fields listed above, and are keen to explore new frontiers of World Scientific Publishing, since its inception in 1981, has grown to condensed matter physics in collaboration with staffs and other members in establish itself as one of the world’s leading academics publishers and the the Unit, are welcome. Good oral and written communication skills in English are required. 78 Asia Pacific Physics Newsletter JOBS

Term KAVLI INSTITUTE FOR THE PHYSICS AND Retirement age 60. The applicants may be accepted as five-year or less fixed term employees if the reviewers judge that final decision should be made MATHEMATICS OF THE UNIVERSE, JAPAN after watching the performance of the applicants on the job. Faculty and Postdoctoral Positions Kavli IPMU probes the deep mysteries of the universe through collaborative Required Documents • Application form (Please download from the link below) research conducted by a range of scientists, including mathematicians, theoretical physicists, experimental physicists and astronomers. • Research accomplishments:1 page(A4size) • Future objectives:1 page(A4size) The institute was established in 2007 as one of Japan’s five elite World • List of publications Premier International Researcher Centers. It became the first member institute of the newly created Todai Institutes for Advanced Study of the • Reprints ; PDF files of no more than 3 papers University of Tokyo in 2011. In April 2012, the IPMU became the Kavli IPMU Deadline: September 30th, 2012 by accepting the donation from the Kavli Foundation, a southern California based philanthropic organization devoted to the promotion of four scientific Contact fields including astrophysics and theoretical physics. Human Resource Development Office,NIMS http://www.nims.go.jp/eng/employment/hdfqf1000000wx4h.html Openings for faculty and postdoc positions are announced in October each year. Visit our website: http://www.ipmu.jp/job-opportunities

INSTITUTE OF PHYSICS, CHINESE ACADEMY OF SCIENCES SUNGKYUNKWAN UNIVERSITY, KOREA The International Young Scientist Fellowship of IOPCAS Post Doctoral Fellow: Quantum Transport in Low Dimensional The Institute of Physics (IOP) of the Chinese Academy of Sciences (CAS) Structures in Low Temperature seeks applicants for its newly established IOP International Young Scientist School of Electronic and Electrical Engineering, and Sungkyunkwan University Fellowship. IOP is a multi-disciplinary research institution focused on Advanced Institute of Nanotechnology, Sungkyunkwan University, Suwon basic and applied physics with a history of more than 80 years. Its current 440-746, South Korea. research activities concentrate on condensed matter physics, optical physics, atomic/molecular physics, plasma physics, soft matter/biophysics, There is an immediate opening for post-doc position in Semiconductor and computation physics. The IOP program of International Young Scientist Nano Device Laboratory (SNDL) of Prof. Gil-Ho Kim in the field of transport Fellowship intends to recognize and support young outstanding researchers measurement of semiconductor heterostructures using GaAs/AlGaAs or of exceptional promise, and encourage ambitious collaborations between IOP nanowire based devices. We are involved in following research areas: high and the international academia. The fellowship position is for one year and electron mobility transistors (HEMT) based on Graphene, GaAs, or nanowire, renewable up to three years. transport phenomena in two/one/zero dimension, nano device fabrication, and electrical characterization of nano-particles and quantum effects of Requirements semiconductor. The project is focused on the transport phenomena in • PhD degree from a university outside Mainland China during the past semiconductor heterostructures down to 15 mK and in magnetic fields up to five years/PhD degree from a university in Mainland China and no less 12 Tesla. We are seeking a strongly motivated post-doc with specialization than one-year overseas research experience during the past five years. in experimental condensed matter physics (e.g. charge transport, Hall • Good academic standing with certain achievements. effect, e-beam lithography, single electron transistor). The group actively • Have a strong spirit of team-work and be cooperative. collaborates with researchers based in Asia (National Taiwan University), US (Colombia University), UK (Cavendish Laboratory) and many other graphene All candidates are required to submit the materials specified below. groups in SKKU and Samsung which will enable the post-doc to establish a • Fill up the online form of International Young Scientist Fellowship at wide range of work contacts during his/her stay in the SNDL. http://hre.iphy.ac.cn/hr/. • A detailed resume including education background, work experience and The selected candidate should have a strong understanding of proposed research plan. semiconductor physics, and should be able to work in a group and individually, must have excellent writing and speaking ability in English, • Three recommendation letters sent directly to IOP by the referees. should be able to prepare reports, presentation etc. The candidates with back ground in simulation of quantum heterostructure will be given priority. Applicants are encouraged to pick a sponsor from the IOP faculty members. If the applicant can not determine at the beginning, we will suggest one Interested candidates should submit a detailed CV along with a covering according to his or her research background. A selection committee will letter replying to this advertisement to the email address mentioned convene and evaluate the applicants twice a year. below. Please include the details (email address) of three experts whom, if Contact contacted, can give a better judgment about your skills. All the electronic materials can be submitted to Miss Qi Fu (iysf@iphy. ac.cn). Signed original letters and documents should be mailed to: Miss Qi Contact: Prof. Gil-Ho Kim, E-mail: [email protected] Fu, Institute of Physics, Chinese Academy of Sciences P.O. Box 603, Beijing 100190, P.R. China APPN JOBS accepts ads from organisations and individuals. To submit, send e-mail to [email protected] For more information, and to register, please visit http://hre.iphy.ac.cn/hr/. September 2012, Volume 1 No 2 79 SOCIETIES List of Physical Societies in the Asia Pacific Region

South East Asia Theoretical Physics Indonesian Physical Society Association (SEATPA) President: Dr. Masno Ginting President: Phua Kok Khoo Address: d/a Pusat Penelitian Fisika LIPI, Komplek Puspiptek Serpong, Address: Nanyang Executive Centre #02-18, 60 Nanyang View, Tangerang 15314, Indonesia Singapore 639673 http://hfi.fisika.net E-mail: [email protected] http://www.seatpa.org Israel Physical Society President: Prof. Yigal Meir Association of Asia Pacific Physics Societies Address: Technion City, Haifa President: Shoji Nagamiya E-mail: [email protected] Address: Physical Society of Japan, 5-34-3 Shinbashi, Minato-ku, Tokyo, http://www.israelphysicalsociety.org 105-0004, Japan E-mail: [email protected] Physical Society of Japan http://www.aapps.org President: Prof. Yashichiro Iye Address: Yushima Urban Building 8F, 2-31-22 Yushima, Bunkyo-ku, Australian Institute of Physics Tokyo 113-0034, Japan President: Dr Marc Duldig, http://www.jps.or.jp Address: 61 Danks Street West, Port Melbourne, VIC 3207 E-mail: [email protected] Japan Society of Applied Physics http://www.aip.org.au President: Makoto Konagai Address: Yushima Urban Building 7F, 2-31-22 Yushima, Bunkyo-ku, Bangladesh Physical Society Tokyo 113-0034, Japan President: Prof. M. Ali Asgar. E-mail: [email protected] Address: Dhaka Dhaka 1216 Bangladesh http://www.jsap.or.jp http://www.bdphs.org Korean Physical Society Chinese Physical Society President: Y. P. Lee President: Zhan Wenlong Address: The Korean Physical Society, 635-4 Yeoksam-dong, Gangnam-gu, Address: Institute of Physics, Chinese Academy of Sciences, Beijing 100190 Seoul 135-703, Korea E-mail: [email protected] E-mail: [email protected] http: //www.cps-net.org.cn http://www.kps.or.kr

Physical Society of Hong Kong Malaysian Institute of Physics President: Mao Hai Xie President: Prof. Kurunathan Ratnavelu Address: Physical Society of Hong Kong, University of Hong Kong, Address: Institute of Mathematical Sciences, Faculty of Science Building, Pokfulam Road, Hong Kong University of Malaya, 50603 Kuala Lumpur, MALAYSIA E-mail: [email protected] E-mail: [email protected] http://www.pshk.org.hk Mongolian Physical Society Indian Physics Association President: Prof. Dr. Ts Gantsog President: Dr. S. Kailas Address: P.O. Box 46-337, National University of Mongolia, Address: PRIP Shed, Room No. 4, B.A.R.C.,Trombay, Mumbai India 400085 210646-Ulaanbaatar, Mongolia E-mail: [email protected] E-mail: [email protected] http://www.ipa1970.org.in Nepal Physical Society Indian Physical Society President: Prof. Shekhar Gurung President: Prof. Milan K. Sanyal Address: Trichandra Multiple Campus, P.O.Box No. 2934, Kathmandu, Nepal Address: IACS Campus, 2A&B Raja Subodh Chandra Mullick Road, Email: [email protected] Kolkata 700032, India http://www.nps.org.np http://www.iacs.res.in/ips

80 Asia Pacific Physics Newsletter SOCIETIES

New Zealand Institute of Physics Physical Society of the Republic of China President: Dr. Ben Ruck President: Huang Rongjun Address: Industrial Research Limited69 Gracefield Rd, PO Box 31-310, Address: Room 413, National Taiwan University, No.1 Sec. 4 Roosevelt Road, Lower Hutt 5040, New Zealand 10617 Taiwan E-mail: [email protected] E-mail: [email protected] http://nzip.sbc-school.com http://psroc.phys.ntu.edu.tw

Pakistan Physical Society Thai Physical Society President: Dr. N. M. Butt President: Dr. Amon Address: Room No 205, Technical Block, NCP, Islamabad, Shahdra Valley Road, Address: PO Box 217, Chiang Mai University, Muang District, Islamabad 44000, Pakistan Chiang Mai 50202. E-mail: [email protected] E-mail: [email protected] http://pps-pak.org/ http://www.thps.org

Physical Society of Philippines National Committee of Russian Physicists President: Prof. Gerardo Maxino President: Dr. Leonid V. Keldysh Address: Philippine Physics Society, Physics Department, Maxino College, Address: 119991 Moscow, Leninsky Prospekt, 32a Central Bagacay, 6200 Dumaguete City, Negros Oriental, Philippines E-mail: [email protected] E-mail: [email protected] http://www.gpad.ac.ru http://philippinephysicssociety.org Vietnam Physical Society Institute of Physics Singapore President: Dr. Pher Hong Khoi President: Prof. Kwek Leong Chuan Address: PO box 607, Bo Ho, Hanoi, Vietnam Address: Institute of Physics, National University of Singapore, E-mail: [email protected] 2 Science Drive 3, Singapore 117542 http://www.iop.vast.ac.vn E-mail: [email protected] http://www.physics.nus.edu.sg

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