UCL DEPARTMENT OF PHYSICS AND ASTRONOMY

PHYSICS AND ASTRONOMY 2011–12 ANNUAL REVIEW

PHYSICS AND ASTRONOMY ANNUAL REVIEW 2011–12

Contents Welcome

It is an honour to write this WELCOME 1 introduction standing, to misquote Newton, on the shoulders of giants. COMMUNITY FOCUS 3 Jonathan Tennyson finished his Teaching Lowdown 4 tenure as Head of Department in September 2011 and so the majority Student Accolades 4 of the material contained in this Outstanding PhD Theses Published 5 Review records achievements under his leadership. In addition, Tony Career Profiles 6 Harker is currently acting as Head of Science in Action 8 Department in many matters and will continue to do so until October 2012. Alumni Matters 9 This is due to my on-going commitments with the ATLAS experiment on the ACADEMIC SHOWCASE 11 Large Hadron Collider (LHC) at CERN. Staff Accolades 12 I currently spend a large amount of my time in Geneva and I am very grateful Academic Appointments 14 to both Tony and Jonathan, as well as to other members of staff for helping Doctor of Philosophy (PhD) 15 to make this transition a success. In Portrait of Dr Phil Jones 16 particular I would also like to thank Hilary Wigmore as Departmental Manager and Raman Prinja as the new Director of RESEARCH SPOTLIGHT 17 Teaching for their continued support. Atomic, Molecular, Optical and Position Physics (AMOPP) 19 High Energy Physics (HEP) 21 “Success in such long- Condensed Matter and term, high-impact projects Materials Physics (CMMP) 25 requires sustained vision Astrophysics (Astro) 29 and dedicated work by Biological Physics (BioP) 33 excellent scientists over Research Statistics 35 many years.” Staff Snapshot 38

Underpinning this success is the outstanding quality of scientific research and education within the Department. These form the very core of Departmental life and are fundamental Cover image: The Dark Energy Survey (DES) Imaging Camera to its continued growth and prosperity. Dr Peter Doel and Dr David Brooks with one of the five lenses which will be installed in Scientifically, 2011 has produced the wide field imaging camera for the DES project. The camera will be placed in the Blanco very many exciting results: the ATLAS telescope in Chile and used to investigate dark energy in the Universe. The lens shown in this experiment (mentioned above) has picture is the largest, measuring one metre in diameter. UCL has been heavily involved in the design, planning and construction of the camera, with the five lenses being installed into the produced some very interesting results camera barrel at UCL. The lenses were aligned to an accuracy of ~50 micrometers in tip/tilt (see p12) and the telescope lenses and centering. For further details on this project, see the Headline Research (p7). for the Dark Energy Survey have now Photograph © UCL Learning & Media Services 2012 been delivered to Chile, I saw the crates drifting past my new office on the end Review edited by Katherine Heyworth, [email protected] of an impressively large crane! (see Design © UCL Learning & Media Services 2012 the front cover of this Review and p7).

1 WELCOME

Welcome cont.

Additionally, we have key roles in two missions which have been selected by the European Space Agency as candidates for their ‘Cosmic Vision’ programme.

The EUCLID mission will target Dark Energy, whilst EChO plans to investigate planets beyond our solar system (see p27). Congratulations to Giovanni Tinetti, who was awarded the 2011 IoP Mosely Medal for her work in this area.

These science programmes continue to attract major research funding from a variety of sources. Success in such long-term, high-impact projects requires sustained vision and dedicated work by excellent scientists over many years. I am proud that UCL Physics and Astronomy is able to provide a platform for such success. Our strong engagement with science From left to right: Professor Jon Butterworth, Professor Jonathan Tennyson FRS and policy also contributes to this and Dr Tony Harker. The laser beam shown in the foreground is used to explore quantum was recognised in the case of Jenny mechanics by levitating small objects such as glass spheres. A small-scale version of Thomas, who this year was not only this experiment will be touring UK science festivals in 2012, see p8 for further details. elected to a fellowship of the American Physical Society for her work in neutrino physics, but was also appointed CBE for services to science. Additionally our level of applications both remain As always, the continued growth of congratulations to Des McMorrow healthy. However there is no doubt the department places a strain on our and Alex Shluger who were also that our incoming admissions tutor, physical resources and the challenge of elected to fellowships of the American David Waters, faces an interesting and finding space remains very much on our Physical Society for their work in X-ray challenging time. Our teaching remains minds. But in any case, I am confident diffraction and the atomic physics of excellent and I congratulate Phil Jones, that we will continue to grow as a centre surfaces respectively. Interactions with joint recipient of the Faculty Teaching of excellent physics at undergraduate, the London Centre for Nanotechnology Award, as well as our students for their graduate and research levels and I very (LCN) continue to bear fruit - one of continued strong results. much look forward to the next few years. my earliest engagements as Head of Department was to attend the LCN 5th On a postgraduate level, the UCL Professor Jonathan Butterworth anniversary celebrations, which was Impact Studentship scheme continues Head of Department a very pleasurable introduction to the to have a huge and beneficial effect exciting physics in this area. on our ability to recruit and support excellent PhD students. This has Although this is an uncertain time been enhanced by the gifts of three for undergraduate recruitment due studentships from alumni, for which to the impact of increased fees and we are extremely grateful. Given the other policy changes which are still success of this scheme, UCL is now to be fully understood, I am pleased looking to extend the programme and to report that the size and strength of further sponsorship would be very our undergraduate cohort, along with welcome.

2 PHYSICS AND ASTRONOMY ANNUAL REVIEW 2011–12

Community Focus

3 COMMUNITY FOCUS

Teaching Lowdown Student Accolades

Undergraduate Awards Intake Departmental Awards Cert. in Astronomy–27 Oliver Lodge Prize Best performance 1st year Physics Mr Stefan Blesneag PhD–39 BSc/MSci–119 Halley Prize Best performance 1st year Astronomy MSc/PgDip–10 Mr Sandor-Iozsef Kruk

C.A.R. Tayler Prize Best 2nd Year Essay (joint winners) Mr Liam Cooper & Mr Hao Ding Awards Wood Prize Bachelor of Science (BSc) Best performance 2nd year Physics 15 14 Mr Zhi Wong 12 11 Huggins Prize 9 Best performance 2nd year Astronomy 6 Mr Marco Rocchetto 5 3 David Ponter Prize 1 0 Most improved performance in Department, 2nd year 1 2i 2ii 3 Mr Wei Wang

Master in Science (MSci) Corrigan Prize 30 Best performance in experimental work, 2nd year

25 26 Mr Mario Zacharias 24 20 Best Performance 3rd Year Physics 15 Mr Arnold Mathijssen 10 Best Performance 3rd Year Astronomy 5 5 0 Miss Shaghayegh Parsa 0 1 2i 2ii 3 Additional Sessional Prize for Merit (3rd Year) Master of Science (MSc) Certificate of Higher Most improved performance 3rd Year 15 15 Education Mr Pierre Deludet 14 12 12 Burhop Prize Best performance 4th year Physics 9 9 Mr Jack Hansom

6 6 Herschel Prize 6 Best performance 4th year Astronomy 3 Mr Carl Salji 3 3 2 2 0 0 Brian Duff Memorial Prize Distinction Merit Pass Distinction Pass Best 4th Year project (joint winners) Mr Alexander Bridi & Mr James Bush

Students studying for the UCL Natural Sciences degree have William Bragg Prize the option of majoring in Physics or Astronomy. Currently Best overall undergraduate just over ⅓ of these students study Physics and Astronomy Mr Wei Chao Zhou modules as one of their two first year strands, with roughly ¼ Tessella Prize for Software choosing to major in Physics or Astronomy in their third year. Best use of software in final year Physics/Astronomy projects Mr Dino Osmanovic

4 PHYSICS AND ASTRONOMY ANNUAL REVIEW 2011–12

Faculty Awards Outstanding PhD Dean’s List A commendation to undergraduate students of excellence. Theses Published Mr Shaun Gupta, Mr Christian Gutschow, Mr Jack Hansom, Mr Dino Osmanovic, ‘Springer Theses’ is a new series of publications from Springer, Mr Mark Pickering & Mr Wei Chao Zhou the series publishes the most outstanding PhD research from Jackson Lewis Scholarship (joint winners) universities worldwide. Dr Hannu Wichterich’s thesis was the Mr Arnold Mathijssen (Physics & Astronomy) first from the Department to be accepted, Dr David Kipping’s & Artiom Fiodorov (Mathematics) work has also been published. Postgraduate Taught Prize Mr Marian Breuer

Postgraduate Awards Departmental Awards Carey Foster Prize Outstanding postgraduate research physics, AMOPP Dr Tahir Shaaran HEP Prize Outstanding postgraduate research physics, HEP Dr Matthew Mottram Marshall Stoneham Prize Outstanding postgraduate research physics, CMMP (joint winners) Dr Dara McCutcheon & Dr Marc Warner Harrie Massey Prize Best overall MSc student Ms Linda Cremonesi Jon Darius Memorial Prize Outstanding Postgraduate Research, Astronomy Dr David Kipping Faculty Awards Postgraduate Research Prize Dr David Kipping

Physics and Astronomy prize winners 2011

5 COMMUNITY FOCUS

Career Profiles

Kate Oliver in Science and started reviewing for The Rebecca Duncan Sky At Night Magazine. What’s more, I Communications, Events Head of Progression & and Marketing Manager, got paid for it! Independent Learning, UCL Engineering Hampstead School On the strength of my science writing (MSci Physics 2007) (BSc Astrophysics 2007) experience, I started my first science communication job working at the European Synchrotron Research Facility (ESRF) in the French alps to promote their upgrade to European journalists. Through this job, I learnt French, a lot about X-rays, and a despair of English food! Since then I’ve written educational material for the Institute of Maths and its Applications, worked as a researcher in the science TV department of the BBC, and have now come full circle to work as the Communications Manager in UCL Engineering.

“I went off to study physics at UCL in 2004, with a

I went off to study physics at UCL in dream of being a particle When I was 18, my ambition was to join 2004, with a dream of being a particle physicist and obtaining the the Army as an accountant! If anyone physicist and obtaining the Swedish Swedish prize.” had told me then that I would end up prize. I rapidly realised that I didn’t have working at an inner city London school the brain or maths to plug any holes in with a degree in Astrophysics from UCL, any theory. So I decided to concentrate The highlights of my career so far have I’d have had them certified on the spot! on experiments instead, but still left been visiting the Compact Muon Solenoid My decision to move into teaching came rather disappointed that I wasn’t going to (CMS) cavern, writing the cover story in my final year at UCL, whilst talking to change the world. for The Sky At Night (in the southern a Canadian alumnus on a transatlantic hemisphere) and winning the science While I was knocking quantum physics call! I was working on behalf of UCL as a pub quiz at the RI. I also occasionally into my skull though, I had also written telephone fundraiser and discovered that write Physics World’s Lateral Thoughts – about science for student magazines, entire boroughs of London had Physics keep an eye out for me! and I thought that this might be classes being taught by non-specialists. something I could be superlative at. I The altruist in me balked at this and submitted some comedy pieces to Null I applied for a place on the PGCE in Hypothesis.co.uk, wrote some content for Secondary Science Education (Physics) a coffee-table book, Defining Moments at the Institute of Education.

6 PHYSICS AND ASTRONOMY ANNUAL REVIEW 2011–12

Headline Research

After completing training, I found myself I am immensely proud of my degree The Search for Dark Energy thoroughly in the deep end; with a full from UCL and am eternally grateful Dark energy is thought to make timetable, my own classes and my very to whoever it was that signed off my up 74% of the Universe, with dark own lab. I’ve never worked so hard, or UCAS application. I recently popped in matter making up a further 22%, slept so little in my life! Every hour was a to the Department and whilst much has however the existence of both are new deadline and precious, the students changed, it still felt a little bit like coming yet to be definitively proven. Through the international Dark Energy Survey will be there whether you’re ready for home (or possibly the prodigal daughter (DES) project, scientists hope to be them or not and if you mess it up, it is returning!). Certain elements of my job able to test the existence of both the students who suffer. I loved (almost!) description can be attributed to the work components. every minute, but found that it was a huge I undertook at UCL; from working for the The first step in this project was responsibility. UCL library during the summer holidays, to design and construct a wide- to conducting tours at the ULO. I truly love lens camera which will be installed in the Blanco telescope in Chile. my job. Although working with tomorrow’s This project brings together both I am immensely proud of generation is not easy, no two days are “ instrumental and cosmology my degree from UCL and the same and every conversation you members of the Astro group; from am eternally grateful to have with a student has the potential the initial commissioning, to the intricate data analysis when the to be life changing – for better and for whoever it was that signed telescope is fully operational. worse. off my UCAS application. Professor Ofer Lahav leads the ” project’s science, Dr Peter Doel and Students often ask me “If you’ve got Dr David Brooks used a specially a degree in Astrophysics why are you adapted laboratory here at UCL to In most other jobs, if you can’t make it working in a library?”. I smile and say install the 5 lenses into the camera barrel (front cover). into work, you just work twice as hard that it’s because I like the holidays, but when you get back, or work from home. in reality I am quietly moulding future The next step will be to ship the camera barrel to Chile for Not so with teaching, you can’t just UCL Physics and Astronomy candidates installation. DES will map 300 million shift the timetable back a day and you as it really is a degree that can take you 1 galaxies, over ⁄8 of the sky, with definitely don’t want any students turning anywhere. Even back to school… Dr Sarah Bridle and Dr Filipe up at your door (plus being tired in front Abdalla co-leading data analysis groups. of a computer is manageable, but not so great in front of a class of 30 children with Bunsen burners!)

I decided to slow my pace down a little and what has eventually emerged is my perfect job. I am in charge of the school library, Head of Careers and organise work experience. I take much satisfaction in seeing the difference a really great placement can make to a student’s attitude and aspirations. Plus I get my accountancy fix, as I am also responsible for students’ Economic Wellbeing and Financial Capability education.

7 COMMUNITY FOCUS

Science in Action

The Big Bang Fair The team demonstrated some of the marvels of particle physics, focusing The Quantum The Big Bang Fair is the UK’s biggest on the Large Hadron Collider (LHC) at single celebration of science and CERN and how physicists plan to prove Workshop engineering for young people. The and weigh, or disprove the existence of Fair takes place annually, at a different the Higgs boson. location every year. In 2011 the event If physicists manage to create a Higgs boson event at the LHC, then it will not live long enough to be directly observed The team demonstrated “ and will rapidly decay into a host of other some of the marvels of particle particles. To find and weigh the Higgs, physics, focusing on the it is these other particles which will have Large Hadron Collider (LHC) to be observed. To demonstrate this, the at CERN and how physicists team used 100 brightly coloured plastic plan to prove and weigh, or balls and filled them to various weights, disprove the existence of the thus representing the different particles Higgs boson. ” expected to be seen at the LHC. With a set of weighing scales, children could came to London and members of the then work out the mass of the plastic HEP group ran an experiment at the Higgs boson by balancing it against the Institute of Physics (IOP) stand. other types of particles. Dr James Millen has been awarded grants by both the Beacon Innovation Seed fund and the Institute of Physics to deliver ‘The Quantum Workshop’.

This is a cutting edge experiment, consisting of a tiny glass sphere which is levitated by laser beams in the air. The experiment will be used to facilitate discussions with the public on quantum mechanics and other areas of physics.

The project is scheduled to appear at the Cheltenham and British Science Festivals, along with educational institutions such as the Science Museum. Photograph courtesy The Big Bang

Plastic balls and scales were used to demonstrate the method and mathematical calculations involved in the search for the Higgs boson at the LHC.

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Alumni Matters Headline Research

A Step Closer To Zero By Professor Presidential committees. Currently she is Carbon Emissions Tegid Wyn the Vice President for Academic Affairs at the prestigious Bryant University, Rhode Jones Island and Vice Chairman of the US A new technology has been National Science Board. It was great to developed which enables hydrogen The Annual Alumni reminisce with her about UCL, alumni in to be stored in a cost-effective Dinner took place on the US and with her husband on Welsh and practical manner, potentially the 6 May 2011 and Rugby! Jose-Marie’s father was a soldier facilitating the use of hydrogen as a was attended by 33 during WW2; after the war he became carbon-free alternative to petrol. guests – our largest a leading member of the London Welsh The team of collaborators, including number to date! Rugby Club. I am always pleased to former EngD student Dr Zeynep welcome Alumni back to the Department. We were addressed by Professor Mike Kurban and Professor Neal Charlton who graduated from UCL Skipper, developed a new nano- Physics with a BSc in 1978, and PhD structuring technique called ‘co- in 1980. In an amusing speech he “I hope that many of electrospinning’. Minute micro-fibres related how I was the first to meet him you will attend our next (30 times smaller than a human at UCL, and the last to see him off the hair) are produced to encapsulate premises in 1999! Mike paid tribute to alumni dinner, scheduled hydrogen-rich chemicals (hydrides). his PhD supervisor, T Ceiri Griffiths and for Friday 4 May 2012. This encapsulation allows the so great was our joint Welsh influence ” hydrogen to be released at a that he moved to Swansea University in significantly faster rate and lower 1999. Together with Ian Halliday, Mike temperature, while also protecting rejuvenated the Physics department and Once again, I hope that many of you the hydrides from oxygen and water, is currently a leader of the project to will attend our next alumni dinner, making it possible to handle them produce anti-hydrogen at CERN. scheduled for Friday 4 May 2012. The safely in air. This new nano-material after-dinner speaker will be Professor contains as much hydrogen as the Another highlight this year was the visit of Cyril Hilsum CBE FRS FREng Hon FInstP. tanks currently used in prototype José-Marie Griffiths to UCL. José-Marie He graduated from UCL Physics in 1945, hydrogen powered vehicles. It can graduated with a BSc from UCL Physics having spent two of his undergraduate also be formed into microbeads that in 1973, followed by a PhD from UCL years in Bangor, due to the UCL can be poured and pumped like a Information Science in 1977. Starting her evacuation during the War. In a truly liquid, and used to fill up tanks in a career with the Imperial Cancer Research illustrious career, his last job was Director similar way to current fuels. Fund Laboratories, she has become an of Research at the GEC Hirst Laboratory. internationally acclaimed policy expert, He is also a recipient of the Max Born This technology is being taken to researcher and university administrator prize, the Faraday Medal, the Glazebrook market by spinout company, Cella in the US and has served on several Medal and the Royal Society Royal Medal. Energy Ltd, which has recently won the 2011 Shell Springboard Prize and Energy Storage Challenge.

9 COMMUNITY FOCUS

In Memoriam

Professor Marshall Stoneham FRS (1940–2011)

Born in 1940 in Barrow-in-Furness, he was educated at Barrow Grammar School for Boys and always spoke with pride of the three Fellows of the Royal Society whom it produced – a statistic he attributed to its excellent physics teaching. His undergraduate and postgraduate degrees were taken at Bristol University and in 1964 he joined the Theoretical Physics Division at the Atomic Energy Research Establishment, Harwell. He spent more than thirty years at Harwell, culminating in his role as Chief Scientist of AEA Industrial Technology. Marshall joined UCL in 1995 as the first Massey Professor of Physics and Director of the Centre for Materials Research. He also joined the newly established CMMP group and, along with the group’s first Head Professor John Finney, set about building it up into the major international research group the Department is able to boast about today. He also played a key role in establishing the London Centre for Nanotechnology (LCN). He personally developed diverse projects such as minimally invasive dentistry, odour recognition, diamond film growth and quantum information science- where his new ideas have led to a substantial and ongoing research programme. Alongside his dedication to Harwell and UCL, he pursued outside interests at an exceptionally high level. He was a keen amateur horn player and musicologist, playing in a longstanding wind octet and After a short illness, Professor Marshall Stoneham even at one point performing the phenomenally difficult FRS sadly died on the 18 February 2011, aged 70. solo part of the Strauss Horn Concerto in concert. His Though nominally retired from UCL, he remained prizewinning ‘Wind Ensemble Sourcebook’ was the highly active within the Department, as well as being fruit of many years research in libraries around the President of the Institute of Physics. world. With his wife, Doreen Stoneham, he founded Oxford Authentication, a small company which has A leader in his field, Marshall will be remembered been highly successful in the authentication of fine-art for an enormously diverse range of contributions to ceramics by thermo-luminescence dating. theoretical materials physics. His books, most notably the definitive ‘Theory of Defects in Solids’, were Marshall will be extremely missed as an outstanding highly influential. His status in the field was attested mentor, an encyclopedic source of scientific by the wide network of longstanding collaborators he knowledge, a wonderful collaborator whose incisive maintained, and by a continuing flow of invitations to questioning rapidly established the viability of any idea, give keynote talks at international meetings. and a loyal friend to many in the scientific community.

by Professor Andrew Fisher

10 PHYSICS AND ASTRONOMY ANNUAL REVIEW 2011–12

Academic Showcase

11 ACADEMIC SHOWCASE

Staff Accolades

Departmental Teaching Prize Headline Research & joint winner of the MAPS Faculty Teaching Award Dr Phil Jones Results from the Large Hadron Collider (LHC) “…nominated by Physics and Astronomy undergraduate students for his inspirational 2011 has been a very exciting year for scientists teaching of the third year Lasers and working at CERN’s LHC. Exceeding the most Modern Optics Course…” optimistic expectations, the LHC delivered billions of the world’s highest energy proton-proton collisions. Institute of Physics (IOP) Moseley Medal The first analysis of this data by the ATLAS and CMS experiments produced tantalizing hints of Dr Giovanna Tinetti the existence of the Higgs boson and excluded a “For her work, pioneering the use of wide range of theoretically allowed masses. This infrared, primary transit spectroscopy has left only a narrow strip between 115GeV and to characterise the molecular 127GeV, where a significant excess of events over composition of extra solar planets.” the expected background was observed. This is broadly consistent with the theory expectations for the Higgs boson production.

Queen’s Birthday Honours The HEP group is playing a leading role within Professor Jenny Thomas CBE the ATLAS experiment in the areas of detector operation, online and offline event reconstruction, Awarded Commander of the Order and simulation software. They are also in charge of the British Empire (CBE) for of several key measurements for the Higgs “services to science” search. The team is frantically preparing for the 2012 data taking period, which is expected to provide three times more data than in 2011 and almost certainly the definitive answer for the existence of the Higgs boson. Wolfson Research Merit Award Professor Jonathan Tennyson FRS

For “Molecular line lists for extra solar planet and other hot bodies”

Fellowships of Learned Societies

Institute of Physics Professor Tania Monteiro

American Physical Society Professor Alex Shluger Professor Des McMorrow Professor Jenny Thomas CBE

12 PHYSICS AND ASTRONOMY ANNUAL REVIEW 2011–12

Promotions Resignations

Promoted to Professor Dr Stephen Lynch Headline Research (to take a position as Senior Lecturer Professor Nikos Konstantinidis & EPSRC Advanced Research Fellow, Professor Ruben Saakyan Cardiff University) Saving the Second Law of Thermodynamics Dr Christian Ruegg Promoted to Reader S. Shabbir, J. Anders and co-workers, (to become Head of the Laboratory Dr Mario Campanelli Landauer’s Principle in the Quantum for Neutron Scattering, Paul Scherrer Regime, Phys. Rev. E (Rapid Institute) Communication), 83, 030102 (2011) Retirements If heat could be converted completely into work, all of today’s energy Dr Malcolm Coupland problems would be resolved. Dr Dave Tovee Unfortunately the second law of thermodynamics forbids exactly this.

However, it remains unclear to what extent the second law applies to systems that obey the rules Artist in Residence Joins HEP Group of quantum mechanics. Indeed research in the past decade has suggested that this fundamental law of physics is broken in a strongly In February 2011, Dr Andy Charalambous joined the HEP group as their coupled quantum system, the first Artist in Residence. He is the second to hold such a position within the quantum Brownian oscillator. Department, following Katie Paterson joining the Astrophysics Group last year. Dr J Anders and MSci Student, S Shabbir, collaborated with Augsburg University, Germany, to resolve this paradoxical situation. They realised that quantum correlations between the oscillator and its environment leave the system in a non-equilibrium, ‘squeezed’ state. Crucially, the squeezing process has an associated thermodynamic heat and entropy change. It turns out that when these contributions are treated properly, the second law violation disappears and standard thermodynamics is restored in the quantum regime.

This image, Neutrino 3, is a photographic print recording an ‘event’ from his installation work, Neutrino. In a dark room, lasers would invisibly flash through the gaps of a mobile. Occasionally they would hit the mobile and the resulting curved flashes of light would prove the existence of both the mobile and the lasers.

13 ACADEMIC SHOWCASE

Academic Appointments Headline Research

Minos Re-Enters the Faster Dr Frank Deppisch than Light Neutrino Race Lecturer joining the HEP group, previously based at The University One of the most talked about physics results of 2011 of Manchester was the surprising measurement that neutrinos may break the ultimate speed limit: the speed of light. The OPERA experiment measured the time taken by a beam of energetic neutrinos to travel 732km through the Earth from CERN to an underground laboratory in Professor Andrew Green Italy. Much to everyone’s surprise the measurement Professor, a joint appointment between suggested that the neutrinos arrived 60 billionths of the CMMP group and LCN, previously based at The University of St Andrews a second ahead of when they should if they were travelling at the speed of light.

Does this shocking result reveal new physics or merely experimental error? UCL’s Professor Jenny Thomas and Dr Ryan Nichol are leading the effort to Dr Simon Jolly answer this question by repeating the measurement Lecturer joining the HEP group, at the MINOS experiment in the USA. The scientific previously based at Imperial community are eagerly awaiting initial results, due in 2012, which will either confirm or refute the OPERA measurement – watch this space!

Dr Alexandra Olaya-Castro Lecturer joining the AMOPP group, previously based at UCL on a EPSRC Career Acceleration Fellowship

Dr Jonathan Oppenheim Lecturer joining the AMOPP group, previously based at Cambridge

Dr Meera Parish Lecturer, a joint appointment between the CMMP group and LCN, previously based at Cambridge

14 PHYSICS AND ASTRONOMY ANNUAL REVIEW 2011–12

Doctor of Philosophy Angeliki Kiakotou Neutrino masses from cosmological (PhD) probes (Supervisor: Prof. O Lahav) Headline Research Matthew Austin The nature and structure of the winds David Kipping of galactic O stars The transits of extrasolar planets with Complexity of Grain (Supervisor: Prof. R K Prinja) moons (Supervisor: Prof. A D Aylward) Boundaries in Ceramics: Electrons Reveal it All Daniel Beecher Donnacha Kirk PDF and QCD effects in the precision The practical use of cosmic shear K. P. McKenna, A. L. Shluger measurement of the W boson mass at as a probe of gravity and co-workers, Atom-resolved CDF (Supervisor: Prof. M A Lancaster) (Supervisor: Dr S L Bridle) imaging of ordered defect superstructures at individual Nikolaos Beglitis Aida Mehonic grain boundaries, Nature, 479, First-principles studies of surface defects The role of physics in epithelial 380–383 (2011) of model metal-oxide semiconductors homeostasis and development (Supervisor: Prof. A J Fisher) (Supervisor: Prof. T A Duke) Most solid materials are polycrystalline; Emily Milner they consist of a complex arrangement Simon Binnie of grains within which atoms form The intercalation and solvation of Ab initio surface energetics: beyond a highly ordered structure. Grain chemical accuracy nanocarbons in ammonia and boundaries are the extended defects (Supervisor: Prof. M J Gillan) organic solvents formed at the interfaces between these (Supervisor: Prof. N T Skipper) grains, and they play a crucial role Nicholas Coppendale in determining the mechanical and Manipulation of molecular motion using William Nicholson electrical properties of materials. For a high-energy chirped laser system Studies of the martian upper atmosphere this reason, there has been a great deal (Supervisor: Prof. P F Barker) with the UCL Mars thermosphere and of scientific research directed towards ionosphere general circulation model understanding their atomic structure. Adam Davison (Supervisor: Prof. A D Aylward) The research team constructed a Exploring electroweak symmetry single grain boundary in the ceramic Immacolata Procino breaking with jet substructure at material magnesium oxide by precisely the ATLAS experiment Laser induced molecular axis alignment: orienting and bonding two crystals (Supervisor: Prof. J M Butterworth) Measurement and applications in together. The resulting bi-crystal was attosecond science then characterised using a range Alastair Dunn (Supervisor: Dr J Underwood) of advanced electron microscopy A molecular dynamics study of diamond techniques, complemented by as a plasma facing material for fusion Alexander Richards theoretical simulations. The use of high (Supervisor: Dr D Duffy) Simulation, software and first energy electrons to probe the structure ATLAS physics of the materials allows for spatial Joanna Fabbri (Supervisor: Prof. J M Butterworth) resolution, down to the scale of atoms A mid-infrared study of dust emission (ten billionths of a cm). Tahir Shaaran from core-collapse supernovae These techniques revealed the A rigorous treatment of excitation and (Supervisor: Prof. M J Barlow) chemical identities of all atoms inside quantum interference in laser-induced the boundary. The results offer new Federica Fabrizi nonsequential double ionization of insights into the complex interactions Probing magnetism in magneto-electric atoms and molecules between impurities and grain multiferroics using circularly polarized (Supervisor: Dr C Figueira De boundaries in ceramics, demonstrating x-rays (Supervisor: Prof. D F McMorrow) Morisson Faria) that atomic-scale chemical analysis of complex multicomponent structures in Samuel Farrens David Stock materials is now becoming possible. Optical detection of galaxy cClusters The cosmic origins of carbon and (Supervisor: Dr F Abdalla) the evolution of dust, gas and the Alex Harvey CNO elements in galaxies Electron re-scattering from alligned (Supervisor: Prof. M J Barlow) molecules using the R-matrix method Marc Warner (Supervisor: Prof. J Tennyson FRS) Beyond classical computing: towards Mathew Kallumadil organic quantum information processing Towards a complete magnetic (Supervisor: Prof. G Aeppli FRS) hyperthermia technology as a novel Adam Williams cancer treatment system Positron ionizing reactions & positronium (Supervisor: Prof. Q A Pankhurst) scattering (Supervisor: Prof. G Laricchia)

15 ACADEMIC SHOWCASE

Portrait of Dr Phil Jones

Dr Phil Jones started his academic career by obtaining a BA degree in Natural Sciences at Cambridge University, after which he joined Imperial College to study for an MSc in Applied Optics. He followed this with a DPhil in Atomic & Laser Physics at Oxford University, before moving to UCL in 1998 with his then supervisor, Dr David Meacher.

Having tested out a number of reputable physics departments, Phil has remained at UCL ever since, working as a postdoc in Professor Ferruccio Renzoni’s Laser Cooling Group until 2004, when he was offered a permanent position as a lecturer.

Phil’s early research focused on laser cooling and trapping of atoms and in particular ‘optical lattices’: perfect crystals of atoms held together by laser light at a temperature a few millionths of a degree above absolute zero.

Optical tweezers have a “ He also looks at biological objects, Phil’s future research will continue to wide range of applications, where they are especially promising for build on the optical trapping technique. Phil is particularly quantifying adhesive or motile forces. He has recently started working as a More recently, Phil’s group has also been consultant on a £1M project with the interested in using them studying optical binding, a phenomenon National Physical Laboratory, combining to probe materials such where large numbers of microparticles optics and acoustics to trap microscopic as carbon nanotubes or self-organise into regular structures objects. Specifically, they will be trapping plasmonic nanoparticles. under the influence of laser light. Just microscopic gas bubbles with laser light ” as with cold atoms the colloidal particles and pinging them with ultrasound. The can be held in an optical lattice, with the frequencies of ultrasound produced in advantage that the individual particles the bubble’s response are very sensitive can be seen under a microscope. to its surroundings, so by recording the ‘acoustic fingerprint’ of a single Since starting his own research group, 2011 has been an exciting year for calibrated bubble and then observing Phil still uses light to exert a force on Phil in terms of teaching. His class of how it is altered by a change in the local and trap matter, but now on objects undergraduate students elected him environment, the project aims to turn the rather larger then single atoms using for the Departmental Teaching Award, bubble into a microsensor. In the future ‘optical tweezers’. This is a technique and he also achieved recognition at these bubble sensors could be integrated which allows microscopic objects to be Faculty level through the MAPS Faculty into the ‘lab-on-a-chip’ technology and picked up and moved around by a single Award, made for outstanding provision used for sensitive detection of trace focused laser beam. Optical tweezers of teaching. His class on Lasers and amounts of chemical contaminants or have a wide range of applications, Phil Modern Optics is extremely popular, antibodies. is particularly interested in using them and every year a significant number of to probe materials such as carbon students can be found swapping the pub nanotubes or plasmonic nanoparticles. for a laboratory tour on a Friday evening!

16 PHYSICS AND ASTRONOMY ANNUAL REVIEW 2011–12

Research Spotlight

17

Project in Focus

Positron and Atomic, Molecular, Optical and positronium collisions Aim Positron Physics (AMOPP) To advance the understanding of the interactions of positrons and positronium with atoms and molecules.

The AMOPP group is one of the most which is usually in the form of two Results to Date diverse in the UK, with research gamma-rays of equal energy, according to New advances concern positron- activities spanning the range from the the well-known equation E = mc2, where induced ionisation (with and without fundamental to the applied. Its members m is their rest mass and c the speed of positronium formation, recently study theoretically and experimentally, light. The annihilation probability depends including excitations of positronium and/or of the target) and positronium the interactions of atoms and molecules on the relative velocity of the electron and scattering. with light, electrons and positrons. the positron and, in many situations in Their research impacts on problems nature, positrons may survive numerous UCL Involvement in astrophysics, biological physics and collisions with matter prior to annihilation, UCL is a pioneer and an international environmental science, among others. exciting and/or ionising it along the way, leader in the field. or capturing from it an electron to form positronium (Ps). This is an atom-like The preponderance of bound-state of a positron and an electron, “ structurally analogous to hydrogen with the The Positron and Positronium Beams matter over antimatter in positron replacing the proton – a classical at UCL and their Surprising Results representation is given in Figure 1. the Universe is one of the At UCL, beams of slow positrons (e+) are most fascinating mysteries Approximately 80% of gamma-rays obtained from a β+ emitter (usually Na-22) in science today. detected in positron emission tomography in conjunction with a so-called ‘moderator’ ” (a medical imaging technique known (typically a tungsten foil or a film of frozen as PET) and 95% of the gamma-rays krypton), from which a small but significant released from the centre of the Milky fraction of the positrons emerge with much One area of study is the interactions Way are the result of Ps decay. Once reduced energies. Electric and magnetic of positrons (the anti-electrons) and formed, Ps has ample time to interact with fields are then used to accelerate, positronium (a matter-antimatter matter before annihilating because its confine and transport them away from composite made up of an electron and a lifetime, although of the order of (0.1-100) the high background near the source to positron) with atoms and molecules. The nanoseconds, is still millions of times an interaction region (a gas cell or jet). Group, established around 40 years ago longer than typical scattering times. For Ps atoms formed travelling in the forward by Professor Ceiri Griffith, Dr Godfrey these reasons, knowledge of how Ps itself direction may be further collimated so as ‘George’ Heyland and Professor John interacts with matter is important also for to define a beam whose energy may be Humberston, remains a pioneer and an improving radioprotection in PET, or for adjusted via that of the incident positrons. international leader in the field. During learning about the environment in which A second gas region inserted downstream this time, theoretical and experimental positrons annihilate in outer space. provides the target to the Ps projectiles methods have evolved from lifetime studies of β+ emitted by radio-isotopes embedded in dense media, to the production of beams of positrons and of positronium which enable investigations at well-defined energies and under single collision conditions. Professor Gaetana Laricchia and her team: Dr Simon Brawley, and PhD students Piers Fransman and Michael Shipman describe recent experimental progress.

Matter vs Antimatter The apparent preponderance of matter over antimatter in the Universe is one of the most fascinating mysteries in science today. Positrons are the antimatter counterpart to electrons (same mass, Figure 1. Classical pictures of H and Ps comparing some of their properties. opposite charge), with which they Note: 1 eV = 1.60 x 10-19 J; n denotes the atomic state (n = 1 being the lowest energy state); -27 eventually annihilate, releasing energy 1 atomic mass unit (amu) = 1.66 x 10 kg.

19 RESEARCH SPOTLIGHT

and different detectors help in unravelling Projectile Static Polarisation Exchange Recently, Ps formation in an excited state the various reactions. In this way, Ps (2P) has been found to increase fourfold collision processes may be investigated Electron Attractive Attractive Yes from He to Xe, whilst that of ionisation as a function of energy and insights simultaneous with the excitation of the Positron Repulsive Attractive No gained about how Ps itself interacts with molecular ion exceeds electron impact matter. Figure 2 shows the current Ps Positronium - - Yes results by up to a factor of ~3 for CO2 beam at UCL. and ~5 for N2. Experimentally, one of the simplest Table 1. First order interactions of various quantities to be determined is the total projectiles with a neutral matter atom or 40 cross-section, a measure of the overall molecule. SF 6 ) interaction probability between two 2

m 30

Examples of this rather unexpected result -2 0 colliding particles. Neutral projectiles 0 are shown in Figures 3 and 4. Similarities (such as Ps) may justifiably be have been noted over the whole velocity 20 expected to scatter very differently from range (from 0.6 to 4 a.u., where 1 a.u. charged projectiles (like the positron Ar = 2200000 ms-1) and all targets so far 10 or electron). Table 1 summarises the Total cross-section (1 investigated (He, Ne, Ar, Kr, Xe, H2, H2O, dominant interactions at play for these He N , O , CO , SF ). The correspondence projectiles: polarisation describes the 2 2 2 6 0 extends even to velocities near prominent 0.0 0.5 1.0 1.5 2.0 2.5 Velocity (a.u.) features in the electron data, such as the Ramsauer-Townsend minimum (as Figure 3. Examples of Ps and electron total Ps scatters overall with a for Ar around 0.2 a.u. in Figure 3) and cross-sections for some targets (1a.u. of velocity “ = 2200000 ms-1). Circles: Ps total cross-section; similar probability to that of resonances (as in CO2 around 0.6 a.u. in Figure 4). The former is due to the green line: electron total cross-section. In all a bare electron travelling cases, despite the major differences between incoming and outgoing waves of the at the same velocity. projectiles, the Ps total cross-section is similar in ” projectile propagating in-step (resulting shape and magnitude to the total cross-section in a seemingly transparent target to the of electrons travelling at the same velocity. projectile) and the latter to the temporary distortion of the electron-cloud induced trapping of the projectile by the target by electric interactions between the at a specific energy. Whilst the physical Ps energy (eV) 0 1 5 10 30 50 100 200 300 400 colliding particles; the static interaction reason for these observations is not yet 30 refers to that between the projectile and fully understood, it has been suggested 25

the (screened) nuclear charge of an that the key might be in the polarisation ) 2 m

undistorted target; exchange is a purely of the Ps, resulting in the electron in -2 0 20 0 quantum mechanical phenomenon with Ps being on average closer to the no classical analogue, arising from the target during a collision. Further work is 15 symmetry-properties of the wavefunction underway to delve into this hypothesis 10

of a system (projectile + target) containing (and others) but already the observations Total cross-section (1 5 two or more identical particles. For the provide the means to obtain fair estimates neutral Ps atom, it had been expected of positronium total cross-sections for 0 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 that the dominant interaction would be countless other atoms and molecules, Velocity (a.u.) via exchange, however recent work at based on the huge body of data which is UCL has found that Ps scatters overall available for electron scattering. Figure 4. A comparison of experimental Ps with a similar probability to that of a bare total cross-sections and those for electrons and In the case of positron projectiles, a positrons for CO . Circles: Ps total cross-section; electron travelling at the same velocity. 2 recent focus has been ionisation (with and green line: electron total cross-section; red line: without Ps formation), together with the positron total cross-section. An enhancement is excitation of Ps or of the target. The total seen for Ps around 0.6 a.u., near the well- ionisation cross-section is determined known 2∏u resonance for electron collisions. by counting the individual ions from all ionising processes; the direct ionisation cross-section is measured by detecting It has been proposed that the ions in coincidence with the scattered enhancement is due to ‘accidental positron; and the positronium formation resonances’ between the ionic states cross-section is determined via the accessed via Ps formation and the simultaneous detection of an ion and an potential energy curves of the neutral annihilation gamma-ray. Excitations of Ps molecule. In future plans, as a test, targets or the target are examined by monitoring will be examined for which, according in coincidence the low energy photons to this supposition, ionisation–excitation Figure 2. The current Ps beam at UCL. emitted upon de-excitation. should not play as prominent a role.

20 Project in Focus

Future Accelerators High Energy Physics (HEP) Aim To develop accelerator technology and facilities for both HEP research and wider applications, such as cancer treatment and safe nuclear power. Results to Date High energy particle physics teaches simultaneously providing much greater Installation of the first sections of the us about the underlying nature of the intensities of protons, neutrinos, neutrons FETS high power proton injector at physical universe, and the forces and and muons than is presently possible. RAL; preliminary stages of UCLH proton therapy facility. laws that govern its development, from the first moments of the big bang, through The UCL particle physics group is heavily UCL Involvement to the present day, and far into the future. involved in a number of cutting edge Leading contributions at four separate accelerator projects: Dr Simon Jolly facilities: building UK’s first proton therapy The Large Hadron Collider (LHC) at describes these below. facility; development of FETS diagnostics; leading UK effort on both plasma wakefield CERN is the world’s highest energy acceleration and muon-to-electron collider probing an entirely new energy High Power Proton conversion experiments. region for fundamental particle physics. Accelerators for Neutrino In the past year, world media have been Physics & Nuclear Power full of LHC Higgsteria, speculating on the UCL is involved in developing these new existence of the Higgs boson. The desire The next generation of high energy accelerators in a facility at the Rutherford to answer fundamental questions — such physics experiments will require high Appleton Laboratory called the Front as the origin of mass and the nature intensity beams (100 mA) accelerated to End Test Stand (FETS) (Figure 1). The of the neutrino is what excites people energies from a few GeV to tens of TeV FETS design will be used as the basis for and drives the subject, but to achieve and then focussed down to sub-millimetre Europe’s next generation high intensity these aims often requires paradigm neutron source (the ESS at Lund, Sweden) shifts in technology that have a much and in part, for the new injector (LINAC-4) wider benefit for everyone. There are We hope to be able for the upgraded LHC, as well as for the many examples: the world wide web “ ISIS spallation neutron source at RAL. was invented in CERN in 1991 and to determine whether The UCL group, led by Dr Simon Jolly, is given away for free; mass production of there is a matter/anti- heavily involved in the diagnostic systems superconducting magnets was made a matter difference in the for the accelerator particularly for the 324 reality by the Tevatron accelerator in the MHz, 3 MeV Radio Frequency Quadrupole late 1970’s, resulting in the economical neutrino sector. ” (RFQ), which both accelerates and focuses production of hospital MRI magnets; and the beam. The diagnostic measurements more recently, grid computing technology of the beam’s profile and emittance are key has been utilised by many disciplines, focal points. In order to provide these high to ensuring that the beam’s stability can particularly in the health sector. intensity beams, a new generation of high be controlled to achieve the high energies power proton injectors — comprising the Physicists are already looking beyond the and high intensities required for physics first 20 metres or so of the accelerator — LHC, which in itself took 20 years to reach exploitation. is required. The start of the accelerator fruition. They are developing technologies complex is critical in establishing a beam which will drive discoveries 10-30 years These high intensity proton beams are vital of sufficient intensity and appropriate down the line, in which a future generation components in two future UCL projects, led stability for further acceleration. of UCL undergraduates will ultimately become involved. The LHC is the highest energy collider in the world and much of what is known about fundamental particles has been learnt from studying these highest energy collisions. However, studying very rare interactions such as those of the neutrino at lower energies can also provide exciting insights into particle physics. The knowledge from these rare interactions has come from developing proton accelerators of the highest intensity, rather than energy. The future of high energy physics will require the development of smaller, cheaper Figure 1 accelerators capable of achieving even Engineering layout of the Front End Test Stand (FETS) higher energies than the LHC, whilst accelerator at RAL, showing (from left) the ion source

21 RESEARCH SPOTLIGHT

accompanying neutrinos. Different theoretical models exist which vary by many orders of magnitude in their predictions for the rarity of such decays: from the extremely rare — about 1 in 10 billion — to the exceptionally rare i.e. 1 in 1018! Therefore to pin down the nature of the underlying physics, we need to able to make studies of up to 1018 muons (this is almost 0.2 µg of muons) in a controlled environment which requires a MW beam of protons to strike a target 24/7 for a year. This study will be done with the COMET experiment (Figure 2) and will look for the neutrinoless transition of muons (in a muonic atom) to electrons that are released with a distinct energy almost equal to the rest mass of the muon. In addition to their use in particle physics, Figure 2 high power proton beams have the A schematic of the COMET experiment showing the interaction of a high intensity proton potential to play a critical role in future beam (from the left of the figure) with a target producing muons and pions. The muons and energy provision. Conventional nuclear their decay products are tracked using the detectors on the right of the figure. reactors burn uranium but alternatives need to be found: there is justifiable public apprehension about long term by Dr Ryan Nichol, Professor Jenny phenomenon and high intensity proton waste disposal, the potential for accidents Thomas and Professor Mark Lancaster. beams with MW of power are needed to and nuclear proliferation. Thorium offers A high intensity proton beam incident on do this. a very attractive alternative as it does a stationary target will produce a large Such MW proton beams are also needed not produce plutonium, so cannot be number of charged pions which will to produce large numbers of muons, weaponised and requires an external decay to muons and muon neutrinos. It the group will study these decays in source of intense neutrons to become has already been observed, through the exceptional detail in order to elucidate fissile. These are provided by a high phenomena of ‘neutrino oscillations’, that the physics above LHC energies. So far, power proton beam striking a spallation a neutrino beam of a given flavour (e.g. a after 60 years of experimentation, every target, controlling the reactor and allowing muon neutrino) is actually a superstition of muon decay ever observed has been it to be switched on and off. The same three distinct quantum states and a beam’s accompanied by neutrinos. However beam of neutrons can also be used to flavour at a given time and distance in all theoretical models explaining the transmute the long-lived radioactive depends on three factors: the relative fundamental unification of forces, it waste to much less harmful, shorter- fractions (defined by a mixing matrix) of is predicted that, although extremely lived isotopes, significantly reducing the these three quantum states; the masses rare, muons should decay without difficulties of long term waste disposal. of the three quantum states; and crucially, a parameter which encodes whether (neutrino) matter and (neutrino) anti-matter are exact mirror opposites of each other. By measuring the evolution of the neutrino 0.7 1.0 beam’s flavour extremely accurately, over 3 long distances (several hundred km), we

hope to be able to determine whether there E z is a matter/anti-matter difference in the (GeV m neutrino sector. It is such a difference that 0 0.5 X (mm) is needed to help explain why we live in a -1 ) universe dominated by matter and why all Energy (TeV ) the anti-matter created at the start of the universe disappeared in the time it takes to -0.7 -3 0 make a cup of tea. We are yet to observe -4 -2 0 0 200 400 600 any phenomena that have a sizeable Z (mm) L (m) asymmetry between matter and anti-matter and we hope the mysterious neutrino Figure 3 world will provide precisely this type of Accelerating field (left) and energy gain (right) produced by a plasma wakefield accelerator.

22 PHYSICS AND ASTRONOMY ANNUAL REVIEW 2011–12

Proton Driven Plasma accelerated. Wakefield Acceleration The UCL group, led by Professor Matthew Wing, is helping to develop Whatever the LHC may find, it is the plasma cell, as well as designing the almost certain that we will need to both diagnostic systems to measure the beam go to higher energies and probe the energies. Observing significant energy phenomena in more detail to elucidate changes of about 1 GeV in the electron what the underlying theories are. beams would validate the concept and For example, if the Higgs is discovered pave the way forward for far cheaper and higher energy particle accelerators. at the LHC, it will be vital to determine Figure 4 whether the Higgs decays precisely Dose deposition for X-rays and protons: note The UCL Proton Therapy as we think it should, requiring an the sharp Bragg Peak in the proton energy accelerator to collide electrons and loss curve. Cancer Facility positrons at high energies. The cost of Modern cancer treatment is largely going to higher energies is largely in civil laser, leads to an oscillating electric field a combination of tried and tested engineering as it will not be economically called a wakefield which can be used techniques: chemotherapy is used to viable to build future accelerators larger to accelerate another beam of charged poison the cancerous cells, combined than the LHC. Therefore it is vital that particles (Figure 3). So far this technique with radiotherapy to irradiate the tumour accelerators of the next generation has largely been confined to theoretical with 6-14 MeV X-rays. In some cases, the are much smaller. To achieve higher simulations and it is vital that the majority of the tumour can also be removed energies in shorter distances requires technique is demonstrated experimentally through surgery. The shortcomings of a much higher electric field gradient, of if it is to form the basis of next-generation these techniques are well known: surgery high energy accelerators. is invasive and healthy tissue can often be UCL is playing a leading role in such an removed at the same time; chemotherapy experimental test. The Proton Driven poisons the entire body, rather than only Whatever the LHC may “ Plasma Wakefield Acceleration (PDPWA) the cancerous tissue; and radiotherapy find, it is almost certain that experiment at CERN will use the existing damages the surrounding tissue, in some we will need to both go to CERN SPS accelerator (that is also used cases irreparably, due to the width of the to inject beam into the LHC) to drive a X-ray beam and the dose deposition profile higher energies and probe plasma wakefield within a 10 m plasma of X-rays in matter. Radiotherapy requires the phenomena in more cell. A 10 MeV electron bunch will be beams from as many as 6 different detail to elucidate what the injected behind the protons: as the proton directions, which overlap to give a more beam loses energy creating the plasma precise dose to the tumour. However, a underlying theories are. ” wakefield, the electron bunch will be new facility is planned for UCLH that will

the order of GeV per metre, as opposed to the tens of MeV per metre which is possible at present. One potential method of achieving this is called plasma wakefield acceleration. This would allow the required energies to be reached in a few hundred metres rather than tens of kilometres.

This new technique makes use of the enormous electric fields that can be generated within plasmas. A plasma is created by heating a gas until the electrons become energetic enough to travel freely, leaving the gas fully ionised. By forcing the electrons out of certain regions of the plasma, leaving only the positively-charged ions, enormous electric fields in the GV per metre Figure 5 range can be produced. Stimulating Dose deposition cross-sections for treatment of child medulloblastoma of the spine, using this charge separation with a beam conventional radiotherapy (left), and proton therapy (right). Note the enormous reduction in of charged particles, or a high power dose to vital and sensitive organs such as the heart and bowels.

23 RESEARCH SPOTLIGHT

Figure 6 Artists impression of the new UCLH proton therapy cancer facility. utilise protons in place of X-rays. down to fractions of a millimetre, but the pitch, close to the main UCL campus. The idea to use protons has its roots in main advantage comes from the energy particle physics research: the first proton deposition profile. X-rays deposit energy An artist’s impression of the new accelerator for treating cancer was built broadly uniformly along their path, which UCLH proton therapy centre is shown by the Fermilab High Energy Physics means that tumour and surrounding in Figure 6. The centre will bring Laboratory in Chicago and deployed in tissue receive a similar dose. together some of the world’s leading California in the late 1980’s. Sadly the Protons, on the other hand, deposit a specialists in complex cancers and UK has been slow to catch up but, along significant fraction of their energy in the construction is due to begin in 2012, with Manchester, UCL has recently been last few millimetres of their path: this with the first patients hopefully being given the funds from the NHS to provide is called the Bragg peak and means treated in 2017. Along with a number the UK’s first high energy proton therapy the damage to surrounding tissue is of other departments within UCL, the centres. significantly reduced (Figures 4 & 5). HEP group is heavily involved in the This is particularly important for treating development of the UCLH facility. The Proton therapy is an advanced form of brain or spinal cancers in children, group is bringing its expertise from high radiotherapy, which can target tumours where damage to growing organs or energy particle physics accelerators far more precisely than conventional surrounding areas of the brain can have and detectors to help in the accelerator methods. It is particularly beneficial permanent side effects. design and particularly in providing for many child cancer cases, but is diagnostic detectors that can monitor also used to treat brain cancers, head There are currently no high-energy the level of secondary radiation, from and neck cancers and sarcomas. The proton therapy facilities in England. neutrons. The design of the facility is a reason for the significant improvement in Clatterbridge in Merseyside offers low challenging project, since protons are treatment of protons over X-rays is due energy eye treatments and patients who delivered to the patient through 200 to the beam size and the dose deposition require treatment for other tumours must tonne gantries that are 3 stories tall, but profile of protons. Proton beams can be be treated conventionally or sent abroad. a successful facility will provide cutting made much smaller than conventional The UCL facility will treat as many as edge treatment to patients in the UK for radiotherapy beams: while an X-ray 2,000 patients per year, including many the first time. beam is normally a few centimetres in children from Great Ormond Street. It will diameter, proton beams can be focused be based on a site as large as a football

24 Project in Focus

Photophysics and device applications of organic Condensed Matter and semiconductors and Materials Physics (CMMP) related nanostructures Aim To achieve greater understanding of the The CMMP group is one of the largest physics underpinning nanostructures of Organic Semiconductors and solution-processed advanced materials condensed matter groups in the Nanostructures: From Displays for optoelectronics and photonics. UK, currently comprising around 90 to ‘Quantum’ Optoelectronics This will facilitate new and improved members. Their research spans a wide and Photonics applications. spectrum of subjects including quantum The most interesting physical properties Results to Date computing, organic electronics, of these materials are determined by Organic LEDs with visible and near- superconductivity, the physics of the infrared emitting spectra, white- the formation of a partially delocalised Earth’s deep interior, biomagnetism emitting light-emitting diodes, solar π-electron system that originates from cells, nanostructuring of organic and nanoscale imaging. The group the lateral overlap of the p orbitals, semiconductors via optical near-field and plays a leading role in many national directed perpendicularly to the bonds scanning thermal probes, high-mobility and international projects, such as the between adjacent carbon atoms. In semitransparent field-effect transistors. development and exploitation of x-ray the case of linear polymers, which UCL Involvement and neutron scattering instruments. often include aromatic rings as in Spans across several departments In addition to this, they are among poly(p-phenylene vinylene), PPV, and and faculties. Activities range from the founding members of the London analogues, the π-orbital develops investigation of the theoretical aspects Centre for Nanotechnology (LCN), a along the chain, with an intrinsic one- of the basic energetics of the materials, to the synthesis and characterisation of multidisciplinary enterprise concerned dimensional (1D) character. However, novel materials and their incorporation with the design, fabrication and the effective delocalisation of the orbital in devices (displays, solar cells, analysis of nanoscale systems for the or ‘conjugation’ does not extend for the photodetectors, transistors, optical purposes of information processing, whole polymer chain, it is interrupted by amplifiers, and lasers). healthcare, energy and environment. morphological defects, such as kinks and They also play an important part in twists of the chain, or chemical defects, the Thomas Young Centre (TYC), an such as differently bonded carbons, interdisciplinary alliance of London carbonyl moieties, cis linkages, or inter-chain states and excitations such research groups, working to address substitutions which limit the extent of the as aggregates and excimers. Further electron (or hole) wavefunction. challenges of society and industry confinement of the excitations, either through materials modelling and the charged or neutral, may arise from theory and simulation of materials. self-localisation induced by geometric relaxation of the soft polymeric chains, One topic of interest to the group is “Conjugated polymers, and from electron correlation effects. the study of organic semiconductors. oligomers and derivatives The latter are evident, for example, in These materials display a variety the relatively high binding energy (> 0.2 of novel physics and have potential can be regarded as eV) of electron-hole pairs (excitons). applications ranging from light- portions of graphene” Strong non-linear effects, ultrafast emitting diodes (LEDs), to applications thermalisation of optically excited states, for energy generation (such as and disorder-mediated processes, are other important aspects of the physics photovoltaic diodes, PVDs), logics Polymeric semiconductors are then, by of these systems. In spite of a relatively (i.e. field-effect transistors, FETs), their very nature, disordered materials, localised extent of the wavefunction of photonics (optical amplifiers, lasers) containing conjugated segments of charged excitations in most (amorphous) and potentially, single-photon emitters different lengths, and hence with different polymeric semiconductors, electric for quantum cryptography and related electronic properties. In addition, the 1D charge can move through the extensive areas. Professor Franco Cacialli character of the π-orbital is substantially π-electron system and transfer between leads a research group which focuses reduced in the solid state or in solutions different molecules, under the action of on organic conjugated semiconductors. prepared with poor solvents, where the an electric field. When electrons and He describes the group’s current molecules’ close proximity may favour holes collide, they can bind together to research in this article. the formation of relatively extended form excitons that can decay radiatively.

25 RESEARCH SPOTLIGHT

It is possible, therefore, to use these Supramolecular Architectures materials to fabricate light-emitting and Interactions devices. Conversely, excitons can The focus of this activity is on investigation be generated by absorbing light and of the influence of supramolecular then be ionised at polymer/polymer or architectures and interactions (driven by electrode/polymer interfaces, allowing for secondary, non-covalent forces) on the fabrication of photovoltaic cells. photophysical properties of the materials. The possibility of turning these interesting This will elicit a deeper understanding of properties into useful devices is important their properties, leading to an enhanced and goes beyond the relevance of the control of the device properties. application as such. In the first place, The electronic and optical properties of it creates the motivation for substantial conjugated polymers (CPs), are in fact research investment. Secondly, some controlled both by the primary molecular devices are in fact specialised scientific structure and by supramolecular tools in their own right, allowing interactions in a way similar to that in sophisticated measurement of certain which secondary and ternary structures material properties. This is the case, are fundamental to the function of for example, of the charge mobility in proteins. The ability to manipulate the Field-Effect Transistors (FETs), of the local molecular environment is thus luminescence efficiency and time decays crucial to access fundamentally new in Light-Emitting Diodes, LEDs, of charge classes of organic functional materials generation via exciton splitting processes with unprecedented properties and in PV cells, and of spontaneous emission performance. Although there has been Figure 1 rates in optical microcavities. The centre-figure is an atomic force microscopy much progress in the last twenty years image of poly-p-phenylene (PPP) rotaxanes, Interestingly, conjugated polymers, on the nanoscale control of the local whose chemical structure is shown at the oligomers and derivatives can be environment for functional molecules, bottom.The top image shows the van der Waals regarded as ‘portions of graphene’, the this still requires more research on the surface of the energy-minimized structure of very material that has been at the focus interactions between other molecular units arotaxane with two rings threaded on each polymer chain. (Reprinted with permission or species, and with the electrodes. of much attention (and a Nobel prize for from Nature Materials, 1, 160 - 164 (2002)). physics) in the last few years. The influence of such interactions is wide ranging, affecting properties as diverse From Supramolecular as luminescence, electrical transport, the properties of molecular materials, not Architectures to Device Physics and chemical and mechanical stability. only in today’s most common optoelectronic and Nanostructures Accurate control of such interactions is devices such as LEDs, FETs, and PVDs, needed to allow optimum exploitation of but also in emerging applications. The group’s primary focus of interest is the control of the nature and fate of the excited states generated in these materials, with a view to device applications: from LEDs and displays, to energy (PVDs and thermoelectrics) and quantum devices (e.g. optical amplifiers, lasers, photodetectors, single-photon emitters). In practice, the research branches out into three powerfully interconnected directions: supramolecular architectures, materials and device physics, and nanostructuring of soft matter via non-conventional lithographic techniques such as scanning Figure 2 Chemical structure (top), artistic rendering (bottom), and luminescence efficiencies near-field optical lithography (SNOL) or (EL and PL, right) of a cyclodextrin-threaded poly(p-phenylene vinylene-derivative rotaxane. scanning thermochemical lithography (Reprinted with permission from Nano Letters, 8, 4546-4551. Copyright 2008 American (SThL). Chemical Society).

26 PHYSICS AND ASTRONOMY ANNUAL REVIEW 2011–12

Here, as a model system the team have worked mostly with rotaxanes (Figure 1). These are inclusion complexes in which conjugated polymers are threaded through cyclodextrin rings, and then capped at the end to prevent unthreading, according to a synthetic route developed by colleagues at the Department of Chemistry at Oxford. With their help, Professor Cacialli’s team have been able to show that when various families of polymers are threaded Figure 3 inside cyclodextrins, these act as spacers Near-infrared emitting materials and light emitting diodes (Reprinted with permission from Nano Letters, 11, 2451-2456. Copyright 2011 American Chemical Society.). which prevent the close face-to-face alignment of the rings. They result in materials with higher luminescence efficiency and a blue-shifted emission, which is also tuneable as a function of the ‘threading ratio’ i.e. the number

“The ability to manipulate the local molecular environment is thus crucial to access fundamentally new classes of organic functional materials”

of rings per polymer repeat unit. In addition to confirming the effectiveness of the cyclodextrins at suppressing the detrimental intermolecular interactions, the Team, in collaboration with colleagues in Milan, discovered, for example, that rotaxanes feature strongly reduced charge dissociation and polaron formation upon photoexcitation.

This leads to unprecedented ultra-broad gain bands in blends of rotaxanes with commercial emissive conjugated Figure 4 polymers. Construction of a nanoscale device by thermal patterning of a polymer. a) A schematic of the device (a Wollaston wire probe). The inset shows the thermal conversion route of the precursor This result is of vital interest to both polymer, PXP, to fully conjugated PPV, which happens optimally at ~200°C. optical amplifiers, and lasers (both b) Atomic force microscopy (AFM) image, and c) confocal fluorescence of a square grid of PPV optically and electrically pumped). structures with line spacing of 2µm produced by scanning the probe in two perpendicular Potentially there is a high technological directions at 230°C and 10µm/s each line represents a double scan (trace and retrace) of the probe. d) AFM and e) confocal fluorescence images taken of a similar set of structures drawn at impact for optical telecommunications 5µm/s and 250°C. f) AFM image of an isolated line drawn in PPV (single scan). The lines and optical materials since the polymeric were drawn at a temperature of 250°C and a scan speed of 5µm/s on a 15nm thick film. g) The composite materials reported there have cross-section reveals a line width (full-width at half-maximum, FWHM) of 28nm. (Reprinted highly controlled optical properties and from Nature Nanotechnology 4, 664-668 (2009) and Adv. Mat. 21, 1279-1285 (2011)).

27 RESEARCH SPOTLIGHT

could realistically lead to disrupting based materials and Se-containing ones, technologies such as single broadband but collected a much larger set of data optical amplifiers covering the entire that is currently being analysed in what is visible region. For example, these can probably the largest comparative study ever be applied for data transmission by assembled on low-energy gap conjugated wavelength division multiplexing in polymers. plastic optical fibres (POFs), thereby providing a solution to the long-standing Nanostructuring issue of the higher attenuation losses of Conventional high-resolution patterning POFs compared to silica-based fibres. techniques such as electron beam Tuneable optically pumped lasers could lithography or focused ion-beam (FIB) also benefit from these findings because lithography are far too aggressive for the ultra-broadband systems described organic semiconductors (OS), which are have potential for the fabrication of susceptible to degradation when exposed solid-state, compact, optically pumped to energetic beams or subsequent chemical tuneable lasers (CW or pulsed). These treatments. Instead, the Group has shown could realistically be pumped by GaN over the years that near-field optical LEDs, or lasers, thereby providing a microscopes operating in the UV, or thermal variety of new sources easily tuneable fields as applied with scanning probes, over the entire visible spectrum. can generate nanoscale patterns (despite Furthermore, due to the reduced the much larger probes dimension), as charge-generation and the resulting illustrated in Figures 4 and 5. The technique prevention of the related suppression is capable of achieving nanoscale resolution of stimulated emission, these systems and high write speeds simultaneously. represent a significant step towards the realisation of an electrically pumped organic laser.

Materials and Device Physics

Over the last year, a special focus has been placed on materials with relatively low energy gaps, which emit or absorb in the near-infrared (NIR) region of the electromagnetic spectrum. These are particularly significant for LEDs as the region between 700 and 1000 nm provides a window of semitransparency in biological tissues, thus providing both illumination and imaging technology. Additionally they also have photovoltaics applications, as NIR materials can be combined with visible absorbing materials to achieve a better exploitation of the solar spectrum. Members of the CMMP group have Image produced by Dan Credginton (UCL) Credginton Dan by produced Image been working on a large collaborative project (ONE-P) and have researched Figure 5 Artist’s impression of the nanoscale patterns a large number of materials provided by generated by scanning probes. EU collaborators. They have achieved success in particular with porphyrins-

28 Project in Focus

Characterising exoplanets Astrophysics (Astro) Aim Observing and understanding the chemical composition of exoplanet atmospheres. Results to Date The Astrophysics Group is one of the half a solar mass of dust has formed in First discovery of water vapour, methane largest in the UK, consisting of 50 the supernova’s ejecta, equivalent to and carbon dioxide in an exoplanet academic, research and support staff, 170,000 Earth masses! If a substantial atmosphere. A dedicated space mission along with 35 PhD students. The work amount of the dust survives future shock to study exoplanet atmospheres, EChO, selected by the European Space Agency. carried out is diverse; ranging from interactions with the interstellar medium, instrumentation to data acquisition then supernovae could account for a large UCL Involvement and analysis, as well as theoretical fraction of the dust found in the Universe. Leading authors or co-authors of four Nature papers announcing these modelling. The group is involved in a Additionally 2011 was a particularly number of high-profile international discoveries. Leading the science and the active year for two new space missions in payload study of EChO consortium (UK, projects such as the Dark Energy which the group has major involvements; France, Italy, Spain, Germany, Denmark Survey (DES), along with the Herschel final approval from the European Space and US). and Planck space missions. 2011 has Agency (ESA) was received for the Euclid been an exciting year, with the Optical cosmology mission, whilst ESA Phase Corrector for the DES project being Zero approval was given for the EChO shipped to the Blanco 4-m telescope in Exoplanet Characterisation Observatory. will study the atmospheres of transiting Chile (see the Headline Research on p7 Euclid is planned for launch in 2019 and exoplanets as they pass in front of and and the front cover of this Review), as will study dark energy via deep imaging behind the stars they orbit. With over 700 well as exciting, yet surprising results and spectroscopy of distant galaxies. exoplanets already discovered and many from the Herschel space mission through EChO is planned for launch in 2022 and more exoplanet discoveries expected in the discovery of large quantities of dust particles in the ejecta from Supernova 1987A.

Present and Future Space Missions

The Herschel Space Observatory was launched in 2009 and is optimised to detect faint light from dust particles and molecules around stars and in star-forming regions and galaxies. Dust particles are an important component of the interstellar medium found within galaxies, and are crucial to the formation of Earth-type planets, although their origin is still uncertain. While mapping our satellite galaxy, the Large Magellanic Cloud, at far-infrared wavelengths with its PACS and SPIRE Image by ESA/NASA-JPL/UCL/STScI/P.Panuzzo by Image instruments, Herschel detected cold dust Figure 1 emission from supernova (SN) 1987A. Large quantities of dust particles in the ejecta from Supernova 1987A have been detected by the A detailed analysis showed that about Herschel Satellite. This has provided a vital clue to their origin.

29 RESEARCH SPOTLIGHT

planet GJ 581d. Interestingly, this planet does not orbit a canonical G-type star like our own Sun, but rather a much dimmer and colder M-dwarf, clearly challenging any geocentric concept of habitability.

Now the key challenge is moving on from simple discovery, important though that remains, to characterisation: what are these planets actually like, and why are

Credit: ESA C. Carreau Credit: they as they are? As more is learnt about the atmospheres and surfaces of these Figure 2 Artist’s impression of the hot-Jupiter HD189733b. This is the first time molecules such as water remote bodies, we will begin to build up vapour, methane and carbon dioxide have been discovered in the atmosphere of an exoplanet. a clearer picture of their construction, history and suitability for life. It is in the near future, research in this area has Among the exoplanets known, eccentric characterising more bodies, in different gained steadily in prominence. planets no longer appear to be environments, that a detailed planetology Dr Giovanna Tinetti, who is leading the oddities, nor do planets with two ‘Suns’. will be taken out of the Solar System and EChO payload consortium, including Furthermore ‘super-Earths’, planets into the Galaxy as a whole. several European countries (UK, France, with up to ten Earth masses, appear to The observation of the exoplanet Italy, Spain, Germany, Denmark, US) be common around other stars but are atmospheres is at the cutting edge of describes below some of the current completely absent in our Solar System. exoplanet science as first attempts at research in this exciting area, along with The smallest exoplanet known today is characterising their chemical composition future plans. Mars-sized, and a potential candidate for and temperature profiles are currently habitability has already been identified, What are Exoplanets made of?

The science of exoplanets, i.e. planets orbiting a star different from our own Sun, is one of the most rapidly changing and exciting areas of astrophysics. A combination of ground-based surveys (2010) L139 712, and dedicated space missions has resulted in the confirmed detection of over 700 planets.

It now seems likely that nearly all stars et al, Astrophysical Journal, Journal, Astrophysical al, et support planetary systems. Since 1995, the number of planets known has increased by two orders of magnitude.

NASA’s Kepler mission has opened up Tinetti G Credit: the possibility of discovering Earth-like planets in the habitable zone around some of the 100,000 stars it is surveying Figure 3 during its 3 to 4-year lifetime. In addition, Observed and modelled spectrum of the exoplanet XO-1b. The spectrum was recorded with the Hubble Space Telescope during the primary transit of the planet. This observed spectrum can be the new ESA-Gaia mission is expected to explained by water vapour, methane, carbon dioxide and monoxide as the major, active discover thousands of new planets. atmospheric components.

30 PHYSICS AND ASTRONOMY ANNUAL REVIEW 2011–12

under way. The ability to detect planetary Characterisation began with a handful absorb or emit light. These are essential atmospheric features, which only have a of hot giant, gaseous planets, the so when interpreting the results of -4 contrast of around 10 compared to the called hot-Jupiters. Other planets, such exoplanet space mission projects and radiation coming directly from the host as GJ1214b, are now within reach with ground-based observations (Professor star, is quite a challenge. However, for current telescopes. This planet appears to Tennyson, Dr Sergei Yurchenko and exoplanets whose orbits are aligned so be somewhere in between a rocky planet the ExoMol team – see Grant Highlight that they cross the surface of their mother and a gaseous one, with a temperature of on P35). star when viewed from Earth, this has boiling water. proved to be possible. This is achieved Searching for Exomoons by measuring the dip in the stellar light- A series of new techniques have curve when the planet transits in front This activity is been developed at UCL which of the star (or disappears behind it) and “ enable researchers to derive robust repeating the measurement at different underpinned by UCL’s and accurate planetary and orbital wavelengths. In the past few years, the world-leading ability to parameters (Professor Ofer Lahav, exoplanet team here at UCL has been produce the huge lists Dr David Kipping and Ingo in the vanguard of this new phase of of wavelengths where Waldmann). Among the applications, ‘exoplanet characterisation’, which requires hot molecules absorb Dr David Kipping is leading the search a combination of skills and expertise for moons orbiting exoplanets, hence that range from solar system science or emit light. ” exo-moons. Given the right conditions, (Professor Alan Aylward, Professor exomoons may be as fruitful a location Steve Miller and Dr Nick Achilleos) to for the development of pre-biotic or statistical astrophysics (Professor Ofer This activity is underpinned by UCL’s biotic activity as exo-Earths. Lahav and PhD students Ingo Waldmann world-leading ability to produce the huge and Morgan Hollis), lists of wavelengths where hot molecules from ground-based observations (Dr Steve Fossey) to spacecraft measurements (Dr Giovanna Tinetti and Dr David Kipping), and from spectroscopy (Professor Jonathan Tennyson) to instrument building (Professor Bruce Swinyard, Dr Giorgio Savini).

Discovery of Water, Methane and Carbon Dioxide in an Exoplanet Atmosphere

Using data from the Hubble and Spitzer satellites and ground-based telescopes, Dr Giovanna Tinetti, along with international collaborators, has pioneered the use of transit techniques in the infrared where molecular features are the most prominent. As a result of these observations, molecules such Credit: NASA as water vapour, methane and carbon dioxide have been discovered for the first Figure 4 time in the atmosphere of an exoplanet. Artist’s impression of an exoplanet with an exomoon.

31 RESEARCH SPOTLIGHT

A Dedicated Space Mission to Discover the Composition of Exoplanets

Dr Giovanna Tinetti and Professor Bruce Swinyard are leading the effort for a new space mission, called EChO, the Exoplanet Characterisation Observatory. This is currently being assessed by the European Space Agency.

“EChO will provide an unprecedented view of the atmospheres of planets around nearby stars.”

EChO is currently in phase zero and will compete with the other three mission candidates for a launch in 2022. EChO will provide an unprecedented view of the atmospheres of planets around nearby stars. It will study planets that span a range of masses (from gas giants to super-Earths), stellar companions and temperatures (from hot to habitable). Services UCL Learning & Media Credit: Figure 5 EChO will inherit the technology of Kepler Artist’s impression of the EChO spacecraft as designed by ESA that achieves exquisite photometric precision at the 10-4 to 10-5 level in the observation of the target star, and extend that capability into the infrared. EChO will place our solar system in context and will address fundamental questions such as: what are the conditions for planet formation and the emergence of life?

32 Project in Focus

Chromosome Imaging Biological Physics (BioP) Aim High resolution three dimensional images of the structure of chromosomes in the metaphase stage of the cell cycle. Results to Date The BioP group is a virtual research metaphase chromosomes, but even Sample preparation is under way using group, forming a network between those are expected to undergo major fluorescence microscopy to understand experimentalists and theorists across morphological changes from one copy how to preserve the low resolution different research areas within the to another. This situation is complicated structure. Department. further for defective chromosomes, often related to human disease and Professor Ian Robinson, an UCL Involvement genetic abnormalities, where major experimentalist member of the CMMP UCL has a resident group based in the insertions, inversions or deletions group, describes below his recent Research Complex at Harwell, which is may have taken place. Metaphase work on studying the structure of next door to the X-ray beamline where chromosomes will be investigated the human chromosome using X-ray the X-ray imaging measurements will be because they are the most compact imaging. Research has now started in made. compared with other stages of the cell the new labs set up at the Research cycle and thus will be easier to image Complex at Harwell (RCaH). The group with X-rays. The metaphase is also folded chromosome will be helped by is taking a fresh look at imaging, with likely to be the most ordered state of collaboration with topology experts from the chromosome at its focus. The the chromosome. the Danish Technical University (DTU). plan is to build on established imaging methods in order to guide the X-ray The group’s approach to chromosome imaging when that goes live early next structure is therefore to undertake year. The RCaH is located next door to investigations with existing scanning the Diamond Light Source which has “There is no such thing electron microscopy (SEM) methods, in been building the I-13 ‘Imaging and order to understand the issues of sample Coherence’ beamline facility; this will as a single chromosome preparation. Due to the resolution provide the largest coherence lengths to structure scale being targeted, it is planned to date of any X-ray beamline in Europe. ” use samples that are chemically fixed, The biophysical side of the group is with the DNA Platinum stained, and led by Dr Mohammed Yusuf, who is histone proteins labelled with specific training four PhD students in cytogenetic antibodies. It is planned to investigate methods and handling chromosomes. The chromosome is an unusual critical-point and solvent-based drying Dr Joerg Schwenke will join soon as the structure in the sense that we have methods, in preparation. This goes last member of the group and design full knowledge at the two ends of the against conventional wisdom that ‘frozen the X-ray instrument required to orient range of resolution, but not in the hydrated’ samples are the only ones chromosome samples at liquid nitrogen middle. The structures of the DNA, the that would be biologically relevant, temperature in vacuum within the simplest histones and the first level of the decision is defendable because coherent X-ray beam at I-13. integration, the nucleosome, are all of the special situation concerning the known perfectly at atomic resolution. considerable amount of prior knowledge Chromosome Imaging The shape of the whole assembly is of the chromosome. This ‘correlative known at the micron-level resolution microscopy’ may allow synthesis of So far the work has concentrated on from optical (fluorescence) microscopy. multiple resolution scale information. chromosome sample preparation and What is unknown is the structure X-ray imaging, under development fluorescent labelling experiments, using between the 11nm nucleosome and at the Diamond Light Source, will a newly acquired Zeiss fluorescence the 400nm wavelength limit of visible allow additional levels of 3D structural microscope for imaging. The philosophy light. The chromosome’s function is information about the chromosome, is that while much chromosome extremely well known and this indicates perhaps sufficient for a complete picture. imaging has been reported before, a high level of intermediate structure, at going back well over 100 years, the the level of 105 to 106 base pairs, which Project Development chromosome is a living organelle will be the main focus of the study. It is whose structure evolves dramatically At the current stage of the project assumed, moreover, that only three- during the cell cycle. Therefore development, working protocols and risk dimensional images, as will be provided there is no such thing as a single assessments for all methods such as with X-rays, will be meaningfully ‘chromosome structure’. The group has cell culture, preparation of metaphase interpretable. The interpretation of the therefore decided to concentrate on chromosomes, Fluorescent in situ

33 RESEARCH SPOTLIGHT

Figure 1 Fluorescence microscopy image of the chromosomes extracted from a single cell of a human liver cell line. Centromeres of chromosome 1 are labelled with a specific red fluorescent dye. The two red signals label the two copies of that chromosome which are present in metaphase.

hydridisation (FISH), storage of cells in slides for examination by fluorescence chromosome 1 is hybridised to a probe liquid nitrogen, SEM sample preparation microscopy. containing its specific DNA sequence and have been established and the lab work carrying a red fluorescent dye. This probe One of the first results to come from has begun. The group has managed allows identification of the chromosomes the fluorescence microscope is shown to prepare chromosome samples from chosen for further study and will allow in Figure 1. The full complement of a chosen human cell line (obtained the development of separation methods 46 chromosomes can be counted. from the health protection agency) now for them to be isolated. It is planned The AT-rich regions of the DNA of growing in the RCaH cell culture facility to take samples from the fluorescence the structures are stained with DAPI, and following the basic methods for microscope to the SEM microscope to 4’,6-diamidino-2-phenylindole stain, preparing chromosomes mentioned compare the structures. highlighting all the chromosomes in blue, above, spreading them on microscope while the centromere of both copies of

34 PHYSICS AND ASTRONOMY ANNUAL REVIEW 2011–12

Research Statistics Grant Highlight

Publication Summary Professor Jonathan Tennyson FRS has been awarded Research Group Number of publications £1,854,000.24 by the European in refereed journals Research Council (ERC) for Astro 132 ‘EXOMOL – Molecular Line Lists for Exoplanet Atmospheres’. AMOPP 60 CMMP 111 The discovery of extrasolar planets was one of the major HEP 171 scientific advances of the last two decades. Many hundreds of planets have now been detected Active Grants and Contracts and astronomers are beginning to characterise their composition

In the last financial year (Aug 2010 – July 2011), MAPS and physical properties. To do Physics and Astronomy generated 24% of the this requires huge quantities of total research income for the MAPS faculty. The spectroscopic data, most of which MAPS faculty as a whole yielded £34,716,000, is not available from laboratory with Physics and Astronomy contributing studies. £8,436,000. 24% Physics and Astronomy The interdisciplinary ExoMol project will provide a comprehensive solution to this problem by providing Astrophysics spectroscopic data on all University Research Fellowship (URF) (Royal Large Aperture Telescope Technology (ESA) PI: Society) £482,594 PI: Dr Filipe Abdalla Dr Peter Doel £26,766 the molecular transitions of EUCLID Definition Phase(STFC) PI: Dr Filipe PATT Linked Grant (STFC) PI: Prof Ian Howarth importance in the atmospheres Abdalla £53,758 £13,294 of exoplanets. This data will Phase B1 Funding for the UK EUCLID Leverhulme Early Career Fellowship (Leverhulme Programme, to Selection of the Mission in October Trust) PI: Dr Caitriona Jackman £48,688 be widely applicable to other 2011 (STFC) PI: Dr Filipe Abdalla £10,986 RAS Fellowship: Energy Release from problems and will be used for Modelling and Observations of Planetary Magnetospheres (Royal Astronomical Society) PI: Atmospheres: the Solar System and Beyond Dr Caitriona Jackman £50,895 studies on cool stars, brown (STFC) PI: Prof Alan Aylward £700,632 Experimental Particle Physics at UCL (STFC) PI: dwarfs and circumstellar ATMOP: Advanced Thermosphere Modelling for Prof Nikolaos Konstantinidis £3,249,880 Orbit Prediction (European Commission FP7) PI: A Wide-Field Corrector for the Dark Energy Survey environments. ExoMol will also Prof Alan Aylward £194,152 (STFC) PI: Prof Ofer Lahav £1,762,661 be used by scientists who study Clusters, Starbursts and Feedback into the Cosmology: from Galaxy Surveys to Dark Matter Environments of Galaxies (STFC) PI: Prof Michael and Dark Energy (STFC) PI: Prof Ofer Lahav spectra of hot molecules in other Barlow £495,913 £829,994 situations such as combustion. The Dust Enrichment of Galaxies (STFC) PI: Prof Observing Dark Energy (Royal Society) PI: Prof Michael Barlow £326,268 Ofer Lahav £101,260 Quantifying the Dark Universe using Cosmic Dark Energy Survey Collaboration (University of Gravitational Lensing (Royal Society) PI: Dr Sarah Nottingham) PI: Prof Ofer Lahav £300,000 Bridle £273,240 Artist in Residence: Ms K Paterson (Leverhulme COGS - Capitalising on Gravitational Shear Trust) PI: Prof Ofer Lahav £12,500 (European Commission FP7) PI: Dr Sarah Bridle £1,050,000 Cosmology from Surveys (STFC) PI: Prof Ofer Lahav £468,087 Small Award: Universe Today: Cosmology, Astrophysics and Technology in Your Classroom Leverhulme Trust Senior Research Fellowship (STFC) PI: Dr Francisco Diego £7,500 - The Dark Energy Survey and Beyond (Royal Society) PI: Prof Ofer Lahav £48,014

35 RESEARCH SPOTLIGHT

Early Career Fellowship - Probing Cosmological Atomic Magnetometry via Quantum Interference Structure through Novel Signal Processing AMOPP (Royal Society) PI: Prof Ferruccio Renzoni Methods (Leverhulme Trust) PI: Dr Jason Dynamics of Information in Quantum Many-Body £12,000 Systems (Royal Society) PI: Dr Janet Anders McEwen £46,000 Quantum Networks Dynamics (Royal Society) PI: £382,692 Europlanet RI - European Planetology Network Dr Simone Severini £86,750 Creating Ultra-Cold Molecules by Sympathetic Research Infrastructure (European Commission CAVIAR - Continuum Absorption at Visible and Cooling (EPSRC) PI: Prof Peter Barker £1,252,039 FP7) PI: Prof Steve Miller £222,209 Infrared Wavelengths and its Atmospheric Relevance Comets as Laboratories: Observing and Cavity Optomechanics: Towards Sensing at the (NERC) PI: Prof Jonathan Tennyson £396,342 Quantum Limit (EPSRC) PI: Prof Peter Barker Modelling Commentary Spectra (STFC) PI: Prof Pairing and Molecule Formation in Ultracold £814,269 Steve Miller £185,912 Atomic Gases (Royal Society) PI: Prof Jonathan The Miracle Consortium: Modelling the Universe Dr S Bose: Spin Chain Connectors, Entanglement Tennyson £273,240 by Measurements and Mesoscopic Quantum - from Atomic to Large Scale Structures (STFC) Understanding the Spectrum of Ammonia (Royal Coherence (EPSRC) PI: Prof Sougato Bose PI: Prof Steve Miller £557,483 Society) PI: Prof Jonathan Tennyson £12,000 £776,411 Cosmic Acceleration - Understanding Cosmic VAMDC - Virtual Atomic and Molecular Centre Quantum Information Uses of Complex Systems Acceleration: Connecting Theory and (European Commission FP7) PI: Prof Jonathan and Limits of the Quantum World (Royal Society) Observation (European Commission FP7) PI: Dr Tennyson £337,022 Hiranya Peiris £37,500 PI: Prof Sougato Bose £76,260 UK R-Matrix Atomic and Molecular Physics HPC Developing Coherent States as a Resource in Cosmic Acceleration: Connecting Theory Code Development Project (UK-Ramp) (EPSRC) Quantum Technology (EPSRC) PI: Prof Sougato and Observation (STFC) PI: Dr Hiranya Peiris PI: Prof Jonathan Tennyson £300,012 £304,205 Bose £79,725 Phys4Entry - Planetary Entry Integrated Models Leverhulme Trust Senior Fellowship - Bell Philip Leverhulme Prize - Hiranya Peiris (European Commission FP7) PI: Prof Jonathan Inequalities and Quantum Computation (Leverhulme Trust) PI: Dr Hiranya Peiris £70,000 Tennyson £139,200 (Leverhulme Trust) PI: Dr Dan Browne £36,525 Detecting Signatures of Eternal Inflation using ESip - Efficient Silicon Multi-Chip System-in- Abstract Quantum Probability (FQXi) PI: Dr Matt WMAP and Planck Data (FQXi) PI: Dr Hiranya Package Integration - Reliability Failure Analysis Leifer £14,296 Peiris £64,189 and Test (Technology Strategy Board) PI: Prof The E-Merlin Legacy CYG OB2 Radio Survey: Career Acceleration Fellowship (CAF) - Ionisation Jonathan Tennyson £283,488 of Multi-Electron Atomic and Molecular Systems Massive Star Feedback and Evolution (STFC) PI: A Calculated Methane Line List for Characterising Driven by Intense and Ultrashort Laser Pulses Prof Raman Prinja £400,466 Exoplanets and Brown Dwarfs (STFC) PI: Prof (EPSRC) PI: Dr Agapi Emmanouilidou £808,016 UCL Astrophysics Short-Term Visitor Jonathan Tennyson £380,702 Thecosint - Theory of Quantum Computation Programme 2010-2012 (STFC) PI: Dr Giorgio EXOMOL - Molecular Line Lists for Exoplanet and Many-Body Simulation with Novel Quantum Savini £44,489 Atmospheres (European Commission FP7) PI: Technologies (European Commission FP7) PI: Dr Modular Wide Field of View RF Configurations Prof Jonathan Tennyson £1,854,024 Alessandro Ferraro £124,156 (ESA) PI: Dr Giorgio Savini £54,706 Wolfson Research Merit Award - Molecular Line Alternative S-Matrix Approaches for Matter in A Study of Galactic Polarized Dust with Blast Pol Lists for Extra Solar Planet and Other Hot Bodies Strong Laser Fields (EPSRC) PI: Dr Carla Figueira (Leverhulme Trust) PI: Dr Giorgio Savini £80,621 (Royal Society) PI: Prof Jonathan Tennyson De Morisson Faria £310,014 Impact Studentship: Silvia Martinavarro – for £72,000 Electron Correlation in Strong Laser Fields: a Infrared and Sub-Millimetre Study of Evolved CAF - Star Formation and the Ism Evolution Time-Dependent Density Functional Treatment Stars (STFC) PI: Prof Bruce Swinyard £30,288 of Galaxies across Cosmic Time (STFC) PI: Dr (Daresbury Labs) PI: Dr Carla Figueira De Thomas Greve £471,898 URF - Exploring Extrasolar Words: from Morisson Faria £17,937 Terrestrial Planets to Gas Giants (Royal Society) Nanofibre Optical Interfaces for Ions, Atoms and PI: Dr Giovanna Tinetti £421,241 Molecules (EPSRC) PI: Dr Philip Jones £197,819 CMMP Molecules in Extrasolar Planet Atmospheres Photonic Force Microscopy with Nanostructures URF: Computer Simulation of Redox and (Royal Society) PI: Dr Giovanna Tinetti £12,000 (Royal Society) PI: Dr Philip Jones £12,000 Hydrolysis Reactions in Enzymatic Systems (Royal Chemistry in Galaxies at Low and High Redshifts Impact Studentship: Agata Pawlikowska - Bubbles: Society) PI: Dr Jochen Blumberger £202,106 (STFC) PI: Dr Serena Viti £302,053 Sensors for the Micro-World (NPL Management Impact studentship: Modelling Electron Transport LASSIE - Laboratory Astrochemical Surface LTD) PI: Dr Philip Jones £54,359 in Multi-Heme Proteins (PNNL) PI: Dr Jochen Science in Europe (European Commission FP7) Positron Reaction Microscopy (EPSRC) PI: Prof Blumberger £21,587 PI: Dr Serena Viti £145,179 Gaetana Laricchia £604,471 Impact Studentship: a Computational Investigation Investigating the Formation of Glycolaldehyde Positronium - Matter Interactions (EPSRC) PI: Prof of Charge Transfer in Organic Semiconducting in Space (Leverhulme Trust) PI: Dr Serena Viti Gaetana Laricchia £468,305 Materials (PNNL) PI: Dr Jochen Blumberger £117,898 £10,295 Renewal of Collaborative Computational Project 2 3D Radiative Transfer Studies of HII/PDR (EPSRC) PI: Prof Tania Monteiro £64,858 URF Extension - Understanding Gas Transport Complexes in Star-Forming Galaxies (STFC) PI: in Hydrogenases Through Novel Computer Dr Serena Viti £381,854 Quantum Dynamics in Atomic Molecular and Simulations (Royal Society) PI: Dr Jochen Optical Physics (EPSRC) PI: Prof Tania Monteiro Impact Studentship: Camilla Danielski - Probing Blumberger £332,813 £167,723 the Atmospheres of Extrasolar Worlds Around M Impact Studentship: Bio-Inspired Materials for Dwarfs (Associacao Solidariedade E Esperanca) Bridging the Gaps across Sustainable Urban Sustainable Energy (University of Cambridge) PI: PI: Dr Serena Viti £25,000 Spaces (EPSRC) PI: Dr Alexandra Olaya-Castro Dr David Bowler £119,580 £14,902 Integrated Knowledge Centre in Ultra Precision ONE-P - Organic Nanomaterials for and Structured Surfaces (EPSRC) PI: Dr David CAF - Exploiting Quantum Coherent Energy Electronics and Photonics: Design, Synthesis, Walker £391,853 Transfer in Light-Harvesting Systems (EPSRC) PI: Characterization, Processing, Fabrication and Dr Alexandra Olaya-Castro £721,930 Ultra Precision Surfaces - Translation Grant Applications (European Commission FP7) PI: Prof (EPSRC) PI: Dr David Walker £670,810 Brownian Motors, Disorder and Synchronization Franco Cacialli £312,741 in an Optical Lattice (Leverhulme Trust) PI: Prof KTP with Zeeko Ltd (Zeeko Ltd) PI: Dr David SUPERIOR - Supramolecular Functional Ferruccio Renzoni £21,600 Walker £82,261 Nanoscale Architectures for Organic Electronics: a Modelling Condensed Matter Systems with Host-Driven Network (European Commission FP7) KTP with Zeeko Ltd (AEA Technology PLC) PI: Quantum Gases in Optical Cavities (EPSRC) PI: PI: Prof Franco Cacialli £314,284 Dr David Walker £126,409 Prof Ferruccio Renzoni £806,753 Impact Studentship: Directing Crystal Growth with Impact Studentship: Willhelmus Messelink - Many-Body Dark States: from Quantum Dot Arrays Functional Surfaces (PNNL) PI: Dr Dorothy Duffy Advanced Optical Fabrication Techniques (Zeeko to Interacting Quantum Gases (Royal Society) PI: £7,880 Ltd) PI: Dr David Walker £29,811 Prof Ferruccio Renzoni £12,000

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Impact Studentship: Jake Stinson - Stability of Terauniverse ~ Exploring the Terauniverse with Hydrated Sulphuric Acid Molecular Clusters, the LHC, Astrophysics and Cosmology (European and the Nucleation of Stratospheric Aerosols Commission FP7) PI: Prof Jonathan Butterworth for Climate Control (PNNL) PI: Prof Ian Ford £356,475 £23,845 Headline Research IPPP Associateships 2010-2011 - Dr Mario URF Extension - Nanomaterials for Biomolecular Campanelli (University of Durham) PI: Dr Mario Sciences and Nanotechnology (Royal Society) Campanelli £4,000 PI: Dr Thanh Nguyen £146,806 Classical vs Quantum = Experimental Particle Physics at UCL (STFC) PI: URF - Nanomaterials for Biomolecular and Addition vs Multiplication Biomedical Sciences and Nanotechnology (Royal Prof Nikolaos Konstantinidis £1,403,342 Society) PI: Dr Thanh Nguyen £325,058 Higgs-Zap - Understanding the Origin of Mass with M. J. Hoban, D. E. Browne, Bio-Functional Magnetic Nanoparticles: Novel the Atlas Experiment at the Large Hadron Collider. Stronger Quantum Correlations High-Efficiency Targeting Agents for Localised Dr Ilekra Christidi (European Commission FP7) PI: Treatment of Metastatic Cancers (EPSRC) PI: Prof Nikolaos Konstantinidis £33,750 with Loophole-Free Postselection, Prof Quentin Pankhurst £12,824 Phys. Rev. Lett. 107, 120402 (2011) Atlantis Event Display (STFC) PI: Prof Nikolaos Magnetic Targeting of Stem Cells (EPSRC) PI: Konstantinidis £143,166 Prof Quentin Pankhurst £8,346 Support for the UK Car-Parrinello Consortium Atlas Upgrade Project (STFC) PI: Prof Nikolaos John Bell’s famous ‘Bell inequality’ Konstantinidis £183,598 (EPSRC) PI: Prof Chris Pickard £5,716 is one of the cornerstones of our Ex Nihilo Crystal Structure Discovery (EPSRC) URF - Higgs Physics and the Mystery of Particle understanding of quantum mechanics PI: Prof Chris Pickard £1,338,601 Masses (Royal Society) PI: Dr Gavin Hesketh – demonstrating that with quantum Laser Materials Interaction: Ashley Garvin £525,834 systems, one can achieve things (PNNL) PI: Prof Alexander Shluger £42,400 URF - Investigating Neutrino Oscillations with EngD - Advanced Gate Stack and Dielectric Minos and Neutrino Astronomy with Anita (Royal impossible in a purely classical world. in Resistive Memory Material (International Society) PI: Dr Ryan Nichol £452,369 Although first derived in 1964, it Sematech) PI: Prof Alexander Shluger £48,047 URF Extension - Neutrino and Cosmic Ray remains a subject of intense debate Impact Studentship: David Gao - Using Studies with Minos, Anita and Cream Tea (Royal and research, and was an important Computation In Component Development Society) PI: Dr Ryan Nichol £298,804 (Chevron Oronite Company LLC) PI: Prof motivation for the development of Alexander Shluger £86,670 URF - Search for a Vector Boson Fusion Produced quantum computation and quantum MORDRED- Modelling of the Reliability and Higgs Boson at Atlas (Royal Society) PI: Dr Emily cryptography. Degradation of Next Generation Nanoelectronic Nurse £399,633 Devices (European Commission FP7) PI: Prof Studentship for Supernemo Design Study (STFC) Recent work published by PhD Alexander Shluger £382,186 PI: Prof Ruben Saakyan £15,808 student Matty Hoban and Dr Dan Impact Studentship: Laser-Materials Interactions: Supernemo Demonstrator Module Construction Theory and Experiment (PNNL) PI: Prof Browne sheds a new light upon (STFC) PI: Prof Ruben Saakyan £297,427 Alexander Shluger £11,400 this important work. By exposing DIAMOND: Decommissioning, Immobilisation New Frontiers in Neutrino Physics - Wolfson a link between the Bell inequality and Management of Nuclear Wastes for Disposal Research Merit Award (Royal Society) PI: Prof and simple arithmetic calculations: (EPSRC) PI: Prof Neal Skipper £72,233 Jennifer Thomas £75,000 Classical vs Quantum = Addition Electron Gas in Reduced Ionic Insulators and Research Associate to Work on Minos (STFC) PI: vs Multiplication, they derive Semiconductors (Royal Society) PI: Dr Peter Prof Jennifer Thomas £114,442 Sushko £478,269 generalisations of the classic Bell Construction, Calibration and Exploitation of Learning to Control Structure and Properties inequality experiment with a number the Minos Experiment (STFC) PI: Prof Jennifer of Nano-Scale Ferroelectrics Using Defects Thomas £15,075 of surprising features. Their work (EPSRC) PI: Dr Peter Sushko £264,337 strengthens the link between the Royal Society Leverhulme Trust Senior Fellowship Heavy Metal Ions in Multi-Component Glasses: foundations of quantum physics and The Local Atomic Structure and Mechanisms of (Royal Society) PI: Prof Jennifer Thomas £42,010 the Charge Compensation (IHI Corporation) PI: its potential future applications. IPPP Associateships 2009-10 (University of Dr Peter Sushko £7,500 Durham) PI: Prof Robert Thorne £12,000 Modelling Correlated Electron-Ion Diffusion in Nano-Scal Tio2: Beyond Periodic Model and Theoretical Particle Physics Rolling Grant (STFC) Density Functional Theory (EPSRC) PI: Dr Peter PI: Prof Robert Thorne £191,476 Sushko £101,530 Particle Physics Phenomenology (STFC) PI: Prof Theoretical Modelling of Amorphous Electrides, Robert Thorne £343,107 Electride Surfaces, and Quasi-Two-Dimensional Active Materials (Tokyo Institute of Technology) GridPP Tier-2 Support (STFC) PI: Dr Ben Waugh PI: Dr Peter Sushko £257,273 £128,480 Multiscale Modelling of Metal-Semiconductor GridPP Tier-2 Support (STFC) PI: Dr Ben Waugh Contacts for the Next Generation of Nanoscale £35,700 Transistors (EPSRC) PI: Dr Peter Sushko £292,850 GridPP3 Tranche 2 Londongrid UCL Grant (STFC) PI: Dr Ben Waugh £8,100 HEP European XFEL Clock and Control System Development and Maintenance of Atlas (European X-Ray Free-Electron Laser Facility Run Time Tester (STFC) PI: Prof Jonathan GmbH) PI: Prof Matthew Wing £645,926 Butterworth £182,207 Impact Studentship Scott Mandry: Diagnostics for Electroweak Symmetry Breaking and Jet Physics a Proton-Driven Plasma Wakefield Experiment with Atlas at the LHC (Royal Society) PI: Prof (Max Planck Institute For Physics) PI: Prof Jonathan Butterworth £86,247 Matthew Wing £31,627

37 Staff Snapshot

Head of Department Lecturers: High Energy Physics D Browne, C Figueira de Morisson Faria, Professor J M Butterworth A Olaya-Castro, J Oppenheim, Head of Group: A Serafini, J Underwood Professor M Lancaster Astrophysics EPSRC Career Acceleration Professors: Research Fellow: J M Butterworth, N Konstantinidis, Head of Group: A Emmanouilidou M A Lancaster, J A Thomas, R Saakyan, Professor M J Barlow R S Thorne, M Wing Royal Society Fellowship: Professors: J Anders (Dorothy Hodgkin) Readers: A D Aylward, M J Barlow, I D Howarth, M Campanelli, R Nichol, D S Waters O Lahav, S Miller, R K Prinja, Senior Research Associate: Lecturers: J M C Rawlings, B M Swinyard S Yurchenko F Deppisch, S Jolly Professorial Research Fellow: Research Associates: Royal Society University D D Walker B Augstein, C Cassidy, C Coppola, A Davison, A Ferraro, C Hill, Research Fellows: Readers and Senior Lecturers: S Hutchinson, A Kolli, V Laporta, G Hesketh, E Nurse A L Aruliah, S L Bridle, A P Doel, C Lazarou, L Lodi, S Lopez Lopez, Principal and Senior Research I Furniss, G Tinetti, S Viti R Marsh, S Midgley, J Millen, Associates: Lecturers: N Nicolaou, B Walker, A Wickenbrock R Flack, O Grachov, P Sherwood, F Abdalla, N Achilleos, H Peiris, Support Staff: B Waugh G Savini J Dumper, R Jawad Research Associates: Royal Society Fellowship: P Bernat, I Christidi, B Cooper, J McEwen (Newton) Condensed Matter and T Coughlin, E Dobson, J Evans, A Holin, E Jansen, J W Monk, Senior Research Associates: Materials Physics R Prabhu, S Torre, D Wardrope F Deigo, J Yates (Honorary) Head of Group: Support Staff: Research Associates: Professor A Shluger D J Attree, G Crone, J Grozier, R Aladro, R J Barber, T Bisbas, T J Hoare, E Motuk, M Postranecky, P Guio, M Hirsch, O Host, C Jackman, Professors: B M Simmons, M R Warren S Jouvel, D Kirk, M Matsuura, G Aeppli, S Bramwell, F Cacialli, W Nicholson, F Poidevin, B Rowe, T A Duke, A J Fisher, I J Ford, A Green, C Sabiu, T Spain, S Thomas, A Harker, D F McMorrow, Q A Pankhurst, S J Thompson, L Voigt, C J Pickard, I K Robinson, A Shluger, P Woods, J Zuntz N T Skipper Support Staff: Readers and Senior Lecturers: M Bibby, D Brooks, J R Deacon, D R Bowler, D Duffy, T T K Nguyen, J Fabbri, R Heward, D Witherick S W Zochowski Lecturers: J Blumberger, M Ellerby, C Hirjibehedin, Atomic, Molecular, Optical B W Hoogenboom, M Parish, P Sushko and Positron Physics EPSRC Career Acceleration Research Head of Group: Fellow: Professor G Laricchia S Schofield Professors: Research Associates: P F Barker, S Bose, G Laricchia, O Fenwick, F Lopez Gejo, S Hepplestone, T S Monteiro, F Renzoni, J Tennyson A Kimmel, N Kuganathan, S Ling, M Martinez Canales, A Morris, D Ortega Reader and Senior Lecturers: A J Bain, P H Jones Most Research staff are employed through the LCN

38 PHYSICS AND ASTRONOMY ANNUAL REVIEW 2011–12

Headline Research

Hubble Space Telescope Teaching Maps Workshop View of Galaxy Clusters Director of Postgraduate Studies: Superintendent: T S Monteiro R Gollay The international CLASH project is using the Hubble Space Telescope Director of Undergraduate Teaching: Technicians: to obtain deep imaging (in 16 colour R Prinja J Benbow, J F Percival bands) of 25 galaxy clusters. This Director of Laboratories: is one of the largest ever Hubble F Renzoni Administrative Staff programmes. Principal Teaching Fellow: Through the phenomenon of Departmental Manager: M Coupland gravitational lensing, these images H Wigmore are used to study the distribution of Teaching Fellows: Grants Officer: dark matter within the clusters, and D Armoogum, P Donovan M Young to detect extremely distant, magnified Co-ordinator 1st year Laboratory: galaxies in the early Universe. The Examinations Co-ordinator P Bartlett data also enables detailed studies of and IT Support: cluster member galaxies and makes Laboratory Superintendent: K Heyworth it possible to search for high-redshift J O’Brien Finance Officer: supernovae which can help to Laboratory Technicians: D Buck understand the puzzle of dark energy. B T Bristoll, M J Palmer, M A Sterling, Finance and Postgraduate The image shows Abell 383, the first D Thomas Administrator: CLASH cluster to be observed. The Admissions Tutors: N Waller imaging revealed 13 new images, of A Aylwood (Undergraduate), F Cacialli five different sources. These provide Undergraduate Administrator: (MSc), R S Thorne (Postgraduate tight constraints on the cluster mass S Cross research), M M Dworetsky (Astronomy distribution. Certificate) Group Administrator Astro: Using photometric redshifts and K Nakum Programme Tutors: modeling systematic uncertainties S Zochowski (Physics), I Furniss Group Administrator AMOPP & HEP: in the lensing analysis, Professor (Astronomy), D Duffy (MSc), M M C Johnston Ofer Lahav, Dr Ole Host and Dworetsky (Astronomy Certificate) Dr Stephanie Jouvel work on Group Administrator CMMP: measuring the distances to the C Jordan sources detected in the CLASH data University of London Science Centre Organiser: using photometric redshifts, and on Observatory S Kadifachi modeling systematic uncertainties in the lensing analysis. Director: I D Howarth Visiting Professors Manager: and Emeritus Staff: P K Thomas A Boksenburg, F W Bullock, D H Davis, Demonstrators: M M Dworetsky, R S Ellis, M Esten, S J Boyle, S J Fossey J L Finney, M J Gillan, W M Glencross, Computing and Experimental Officer: T C Griffith, C Hilsum, J W Humberston, T Schlichter T W Jones, G E Kalmus, M Longair, K A McEwen, B R Martin, D J Miller, Technical Support: W R Newell, G Peach, P G Radaelli, M Pearson A C Smith, P J Storey, D N Tovee, C Wilkin, D A Williams, A J Willis

39 Notes

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