sign in sign up
<<
Home , Stephen Hawking

THE UNIVERSITY OF NORTH CAROLINA AT CHAPEL HILL

FALL 2015

NEUTRINOS AND THE NOBEL PRIZE

he 2015 Nobel Prize in was awarded to of the University of Tokyo and Art McDonald Tof Queens University in Ontario, Canada in Stephen Hawking and early October for their work on neutrinos. McDonald led the Sudbury Neutrino other physicists attended Observatory (SNO), a project that included a conference on Hawking three members of our department. John Radiation during the week of Wilkerson, the John R. and Louise S. Parker August 24-29 in Stockholm, Distinguished Professor of Physics, Associate Professor Reyco Henning, and Senior Research Sweden. The was Scientist Mark Howe all worked on the SNO Prof. John Wilkerson at the Sanford Underground initiated and co-organized by experiment before coming to Carolina. Research Facility (SURF)(Photo by Benjamin UNC Professor Laura Mersini- Neutrinos are the most abundant particles Brayfield). in the but they interact very weakly Houghton and was co- with other and are therefore difficult before these measurements. sponsored by the University to detect. Nuclear reactions in the Wilkerson, Howe and Henning are now of North Carolina at Chapel should produce large numbers of neutrinos, working on the next big question about but experiments in the 1980’s and 1990’s neutrinos, which is whether they are their Hill, the Nordic Institute only detected about a third to one half as own antiparticles. UNC-Chapel Hill is the for , the many neutrinos as expected. This became lead institution for a major international Department of Applied known as the “solar neutrino problem.” experiment, called Majorana, that will attempt SNO was designed and built to address this to address this question. Mathematics and Theoretical problem by measuring the fluxes of all the Wilkerson also is the inaugural director Physics at the University of different neutrino flavors, something the early of the new Institute for and and the Julian experiments could not do. In 2001 the SNO , Subatomic Matter, and collaboration presented the first clear evidence Symmetries (CoSMS Institute), a joint physics Schwinger Foundation. UNC that the solar models were correct and that institute headquartered at UNC-Chapel Chancellor Carol L. Folt it was the neutrinos that changed flavor as Hill and organized to work on fundamental delivered remarks prior to they propagated through space. The mixing problems at the leading edge of basic physics Professor Hawking’s public between neutrino flavors requires that they have research. CoSMS is a partnership with Duke, , which was not established or expected NC State, and Oak Ridge National Laboratory. lecture on August 24. See article on page 3.

WHAT’S From the Chair ...... 2 In The Lab...... 4 Historic Conference, Historic Challenge...... 2 Student Spotlight...... 4 INSIDE UNC Physics Facts...... 3 Neutrino Day comes to the Triangle...... 5 Physics Corner: Neutrinos...... 3 CoSMS News...... 5 Staff Notes...... 4 TUNL Celebrates its 50th anniversary...... 6

1 FROM THE CHAIR eutrinos are elusive particles and ti-particle. We salute these and all the other dedi- we hire will conduct research at the Triangle detecting them is a tricky business. cated neutrino physicists who labor long hours in University Nuclear Laboratories (TUNL), which Along with our CoSMS colleagues at deep mines to help discover what’s missing from celebrated its 50th Anniversary this month, and Duke,N we are celebrating the success of two dif- the standard model of . See the will teach in our department. ferent neutrino experiments, Super-Kamiokande articles on page one and three of this newsletter Our research and educational missions rely and the Sudbury Neutrino Observatory. These for more on neutrinos. upon federally-funded labs, state-funded classroom experiments were led by Takaaki Kajita of Japan This fall semester, we are excited to be launching teaching, and the generosity of individual donors. and Art McDonald an international search for a new colleague in the This powerful public-private alliance forms the of Canada, who were area of experimental nuclear physics to fill the backbone of great universities like Carolina. jointly awarded the newly-endowed Edward G. Bilpuch Distinguished In a when federal funding is increasingly 2015 Nobel Prize Professorship in Physics. While attending UNC competitive and state budgets are tight, all in Physics for their on a football scholarship, Ed Bilpuch played on institutions of higher education rely greatly on measurements showing three major bowl teams … in the Cotton, Sugar private donations. We would not be the Carolina that neutrinos undergo and Orange bowls. He was elected to Phi Beta or the department that we are without your mixing and therefore Kappa and received both his BS (1950) and his generous commitment and support. I am truly have mass. Ph.D (1956) in physics from our department, and grateful to all of our donors and hope that you will UNC Physics he was a member of UNC’s first class of Morehead consider continuing or beginning to support Professors John Scholars. Ed joined the physics faculty at Duke in the department. Wilkerson, Reyco 1962 and rose there to be the Henry W. Newson Chris Clemens Henning, and Senior Professor of Physics. He served as Deputy Director Research Scientist of the Triangle Universities Nuclear Laboratory With warmest regards, Mark Howe of our de- from 1966 to 1978 and as Director until his partment were part of the SNO collaboration and retirement in 1992. contributed substantially to the key discovery. We are grateful to Ed’s widow, Marilyn S. They are now working on the next big question, Bilpuch, for her generous gift that has established Chris Clemens which is whether neutrinos are their own an- this professorship in his honor. The new colleague Chair, UNC Physics and Astronomy

HISTORIC CONFERENCE, HISTORIC CHALLENGE hysicists have long debated physicists, Stephen Hawking, emeritus Lucasian whether the information Professor and Dennis Stanton Avery and Sally carried by particles falling Tsui Wong-Avery Director of Research in the Pinto a is lost from the Department of and universe forever or whether bits of Theoretical Physics at the , this information continue to exist announced a completely new solution to the in some form. Thirty-two of the information loss paradox. world’s leading physicists gathered The field of theoretical physics has in Stockholm in late August to try changed significantly since Hawking and his to tackle this problem in funda- contemporaries helped define it four decades mental physics, which is called the ago. Mersini-Houghton wanted to bring them information loss paradox. together for a lengthy, in-person discussion to Six days weren’t enough to ignite new ideas and to make sure the work in solve a problem that has stumped the field is passed along completely to the next physicists for 40 years. Still, the UNC-CH Chancellor Folt with Stephen Hawking and UNC Professor generation of physicists. week-long Laura Mersini-Houghton, who organized the conference in Stockholm. “It was very important that when that group Conference in Stockholm, Sweden of people passes the torch to the next generation, was productive. the story of Hawking Radiation and black holes “In science, having disagreements is considered more successful than and information loss is absolutely clear, so that whoever works on this having an agreement because that’s how discoveries are made,” said field from now on will be able to know what the correct way of thinking Laura Mersini-Houghton, associate professor of theoretical physics in is,” Mersini-Houghton said. the College of Arts and Sciences at Carolina and the initiator and main The Hawking Radiation Conference was co-sponsored by UNC-Chapel organizer of the conference. “Science relies heavily on scrutiny. If we all Hill along with the Nordic Institute for Theoretical Physics (Nordita); the agree on one point of view, then that door is shut. There is no room left Centre for Theoretical Cosmology at the Department of Applied Mathematics for inquiry.” and Theoretical Physics at the University of Cambridge; and The Julian “UNC-Chapel Hill has been so fortunate because we have been able to co- Schwinger Foundation, co-hosted by KTH Royal Institute of Technology. sponsor this historic conference with some of the greatest institutes of theoretical physics in the world,” UNC-Chapel Hill Chancellor Carol L. Folt said. Rob Holliday, UNC Office of Communications and Public Affairs A highlight of the conference came when one of the world’s best-known

2 UNC Physics Facts CORNER PHYSICS NEUTRINOS In 2015, there are 85 graduate students in the n the medieval era, the department. search for a way to change lead into gold was the Professor Charles Evans subjectI of alchemy, a branch of research that led through has been named the Agnew Robert Boyle and H. Bahnson Jr. Distinguished to modern chemistry. We Professor of Physics now know that the methods of chemistry cannot effect the transmutation of the elements. In 2015, our department will The energy scales of chemical host our firstNASA Hubble reactions, which involve rearrangement of electron Postdoctoral Fellow, Dr. states in atoms, are far too J.J. Hermes. low. However, in the 20th century, breakthroughs in (much In 2014, UNC was tied (with higher energy) nuclear physics led to the understanding that NC State University) for certain elements transform the 22nd largest class of into others naturally, through graduating seniors in physics a process known as radioactive decay. In a common form of nationwide. View of the SNO detector after installation of the bottom radioactive decay, called beta- PMT panels, but before cabling (Photo courtesy of Ernest decay, a neutron inside of an Orlando Lawrence Berkeley National Laboratory). Roger Wendell, former atomic nucleus spontaneously transforms into a proton, UNC Graduate Student changing the element to the next higher one on the periodic table. In this decay an electron now Assistant Professor at (also called a beta particle) is emitted. However, early measurements of these particles implied the University of Tokyo, was that the total energy was not conserved in beta-decay. Wolfgang Pauli and later Enrico Fermi proposed the missing energy was carried away by awarded the Young Scientist a particle called the neutrino which, in 1956, was experimentally detected. The neutrino Award of the Physical interacts so weakly with ordinary matter Society of Japan in 2014 for that it has taken a long time to measure its properties, and many of the most basic work on Super-Kamiokande. properties remain elusive. For instance, we “The neutrino interacts don’t know the of neutrinos, although so weakly with ordinary Professor Laura Mersini- experiments at Super-Kamiokande and the matter that it has Houghton was recently Sudbury Neutrino Observatory have shown that they cannot be zero. These experiments taken a long time to featured in the BBC-Horizon were recently awarded the 2015 Nobel Prize measure its properties, documentary ‘Which universe in Physics for their results. are we in?’ Neutrinos with mass contradict the and many of the most expectations of the so-called “standard basic properties remain model” of physics, the theoretical framework developed to understand the interaction of all elusive.” particles and fields in existence. The simplest version of the standard model is therefore wrong, and the search for the best way to extend or correct it is the 21st century analog of the ancient search for a way to change lead into gold. Much of basic physics research is aimed in one way or another at this problem.

3 Staff Excellence Award last year, while Business Services Coordinator Cassandra Houston earned Team Player of the Year. Administrative Services STAFF NOTES Manager Shannon Isley received the Personal Achievement Award. “Anything that puts me in the center of attention makes me embarrassed,” team player Houston admitted with a laugh. “But I really did appreciate the award. It’s been a pleasure working with the department, serving here, and watching it grow.” Loftin suggested the idea of staff awards to department Chair Chris Clemens as a way to publically recognize staff efforts and boost morale. Associate Chair Jonathan Engel heads an awards committee that makes its decisions based on nominations from anyone in the department – faculty, Beverly Loftin Cassandra Houston Shannon Isley staff or students. The recognition comes with a monetary bonus. All three recipients said they appreciated their work – generally behind ominations recently closed for the department’s second annual staff the scenes - being acknowledged. achievement awards, inaugurated in 2014 to recognize staff for “I felt accomplished – like I’d really achieved a goal,” Isley said. superior service. The 2016 awards will be announced at the department’s holiday party NDepartment Manager Beverly Loftin received the first Donna Braxton in December.

IN THE LAB STUDENT SPOTLIGHT Physics and political science major NEW MRI METHOD (and math minor) Drew Roberts DETECTS METABOLICALLY spent the summer in Washington, ACTIVE BROWN FAT DC, as a Mather he recent Policy Intern, discovery in working with the adult humans Tof metabolically minority staff of active brown fat, a fatty tissue specialized the US House for dissipating large Committee on amounts of energy in the form of heat, has Science, Space, opened new avenues and Technology. for the treatment of obesity and diabetes. Graduate students Alex Burant (left) and Michael He prepared documents and But progress in studying Antonacci (right) adjust an experimental MRI machine. human brown fat witnesses for hearings on the often has been slowed by difficulties in detecting this tissue. Now, a team International Space Station, of researchers in the Department of Physics and Astronomy, led by Dr. Branca, has developed a new magnetic resonance imaging method that will the EPA, the National Weather help researchers to clearly detect this tissue in humans with unprecedented Service, and the DOE. He says the sensitivity and specificity. This new imaging method, recently described in the Proceedings of the National Academy of Sciences, leverages the internship “allowed me to know exquisite sensitivity of the lipophilic gas xenon, whose nuclear that I would like to end up in the polarization is enhanced up to five orders of magnitude through spin- exchange optical pumping, produce background free in vivo maps of brown science policy world.” fat and its temperature. In collaboration with UNC clinical investigators, Dr. Branca is now using this method in humans to understand how this tissue develops and how it is regulated in the body.

4 Student Life

A live video tour of the Majorana Demonstrator NEUTRINO cleanroom facility at the Sanford underground lab was displayed in DAY COMES the Daily Planet of the Museum of Natural TO THE Science during the Neutrino Day event. TRIANGLE

his year marks the first year in a new tradition of hosting Neutrino Day in the Triangle. Hosted by UNC, the CoSMS TInstitute, and The North Carolina Museum of Natural Sciences, the event featured members and answer session from underground at the In addition to the presentations and live feed of the UNC Physics Department both locally at Davis Campus of SURF led locally by UNC from SURF, attendees were encouraged to take the Museum of Natural Sciences in Raleigh and postdoctoral fellow Christopher O’Shaughnessy part in activities and demonstrations for visitors deep underground in the Sanford Underground and the museum’s Rachel Smith. Despite its depth of all ages. UNC graduate students Gulden Research Facility (SURF) in Lead, SD, explaining nearly a mile below the surface of the earth, the (Joule) Othman and Chelsea Bartram helped the physics of neutrinos and . The SURF laboratory is actually 100 ft in elevation visitors visualize radioactive decay, cosmic rays, Majorana Demonstrator project is based at above the Museum of Natural Science. and the challenges associated with constructing SURF (see page 1). Fittingly, Professor Reyco Henning and legos in a glovebox, simulating the construction In its debut this year in Raleigh, Neutrino Majorana collaborators were remotely displayed of neutrino physics experiments. Thanks to the Day featured talks on neutrinos by NCSU in giant form on the interior of the Daily Planet at unique partnership that the new CoSMS Institute professor and former UNC postdoctoral fellow the Museum for this Q&A session. Visitors also establishes between UNC and local museums, Matthew Green and on Dark Matter by Patrick viewed a live walkthrough tour of the Majorana we can look forward to more great outreach Treuthardt, assistant director of the Astronomy Demonstrator cleanroom facility. programs like Neutrino Day engaging the and Astrophysics Lab at the Museum of Natural The event was a huge success, drawing at least Triangle community. Sciences. The event also included a question 120 participants, and over 1800 at SURF in SD.

CoSMS NEWS

he Institute for Cosmology, Subatomic Matter & Symmetries (CoSMS) held a retreat May 7 Tat the NC Botanical Gardens in Chapel Hill. More than 40 Institute faculty from UNC, Duke, NCSU, NCCU, and Oak The CoSMS Institute is developing a series of received support from the UNC Office of Research Ridge National Laboratory attended the retreat. international workshops exploring fundamental to launch the inaugural workshop in this series. The day started with a series of lively “Elevator” questions in physics and mathematics. The We congratulate CoSMS Institute colleagues talks by each Institute member on their current unifying theme is “From the Abstract to Practical” Professors Kate Scholberg and Chris Walter research activities. Sessions were held to identify – translating the leading edge of fundamental at Duke University who are members of the and discuss key science questions to be addressed theory into practical experiments and empirical SuperKamiokande collaboration led by Taakaki in the coming decade. In the afternoon working observations. The overarching goal is to update Kajita who shared the 2015 Nobel Prize for groups addressed upcoming Institute activities the local, national and international community Physics for the discovery of neutrino oscillations. and opportunities. on progress in fundamental theory. CoSMS has

5 Non Profit Organization

US POSTAGE PAID Chapel Hill, NC Permit Number 177 UNIVERSITY OF NORTH CAROLINA AT CHAPEL HILL Phillips Hall, CB #3255 120 E. Cameron Ave. Chapel Hill, NC 27599-3255

TUNL CELEBRATES ITS 50TH ANNIVERSARY JOIN US at the forefront of physics and astronomy with a financial On November 6-8, 2015, we gift to the department. celebrated the 50th anniversary of the The Department of Physics and Astronomy Excellence Fund helps enhance our world-class programs in research and formal agreement education by supporting visiting speakers, providing seed funds between Duke for new instrumentation, and expanding research experiences University, NC State for our students. University, and UNC that established the Gifts of any size will greatly increase our ability to support outstanding faculty and students. Triangle Universities Nuclear Laboratory. To give online, visit www.physics.unc.edu/donate/ TUNL’s beginnings in To give via check, make your check payable to “The Arts and the fall of 1965 coincided with the award of funds by Sciences Foundation” and include “101281 – Physics and the US Atomic Energy Commission to purchase its Astronomy Excellence Fund” in the memo line. Please mail tandem Van de Graaff accelerator. Since then, TUNL your check to: has grown into a multi-faceted, collaborative nuclear The Arts and Sciences Foundation physics research and training program with more than 134 E. Franklin Street $7M in annual external funding. Its 280+ doctoral CB# 6115 graduates have gone on to a wide variety of careers Chapel Hill, NC in the academic, government, and private sectors. Photo by Lauren Daly/The Daily Tarheel Daly/The Daily Tarheel Photo by Lauren