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Physics Illinois News PHYSICS ILLINOIS NEWS THE DEPARTMENT OF PHYSICS AT THE UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGN • 2007 NUMBER 1 Van Harlingen Exotic relatives discovered named 10th BY RICK KUBETZ playing a major role in the analysis of head of Physics the data, Pitts, along with his team n October, the CDF collaboration— of engineers, postdoctoral researchers, Iwhich includes researchers from the and graduate students, developed University of Illinois—announced at important components in the CDF n July 1, Fermi National Accelerator Laboratory 2006, data acquisition system that made O the discovery of two rare types of this measurement possible. Dale J. Van particles, exotic relatives of the much Harlingen, “To observe a handful of these more common proton and neutron. new particles, we had to sift through Center for Kevin Pitts, an associate professor of Advanced more than 100 trillion Tevatron physics at Illinois, is one of the co- collisions,” said Pitts. “This discovery Study Professor leaders of the CDF physics group of Physics and would not have been possible were performing this measurement. it not for the high-speed processing Donald Biggar “This is the first observation of Willett Postdoc Anyes Taffard and graduate system developed here in Urbana.” the ∑b (“sigma-b) baryon, which is an Another key component of the Professor of extremely heavy cousin to the proton, student Christopher Marino working on Engineering, became the 10th head the CDF high-speed digital processing CDF detector is the “Central Outer much like an atom of iron is an Tracker” (COT), which is heavily of the Department of Physics at the extremely heavy cousin to an atom of system University of Illinois at Urbana- utilized in event identification and hydrogen,” Pitts explained. “We have reconstruction. Pitts, along with Tony Champaign. just added to the mankind’s knowledge discovered two types of ∑b particles, Van Harlingen has spent his entire each one about six times heavier Liss of Illinois, played major roles of the ‘periodic table of baryons’.” in the construction of the COT. professional career at Illinois, joining Utilizing Fermilab’s Tevatron than a proton. The new particles are the Physics faculty in 1981 as an extremely short-lived and decay within “The University of Illinois has collider, currently the world’s most been a one of the leading groups assistant professor. He received his powerful particle accelerator, physicists a tiny fraction of a second. bachelor’s degree in physics in 1972, To overcome the low odds of on the CDF experiment since its can recreate the conditions present inception,” said Liss, who was the and his PhD in physics in 1977, from in the early formation of the universe, producing bottom quarks—which in The Ohio State University. After a turn transform into the ∑ —scientists co-leader of the CDF working group reproducing the exotic matter that b responsible for the discovery of the year as a NATO postdoctoral fellow was abundant in the moments after take advantage of the billions of in the Cavendish Laboratory at the collisions produced by the Tevatron top quark in 1995. “We are proud of the big bang. our contributions to this important University of Cambridge, England, Baryons (derived from the Greek each second. working with Professor John Waldram, One of the largest university work, and as we continue to take word “barys,” meaning “heavy”) are data at unprecedented rates, we look Van Harlingen held a postdoctoral particles that contain three quarks, the groups in the CDF collaboration is research position at the University of from the University of Illinois at forward to many more discoveries in most fundamental building blocks of the coming months and years.” California, Berkeley for three years, matter. The CDF collaboration Urbana-Champaign. In addition to where he worked on non-equilibrium superconductivity and dc SQUID electronics with Professor John Clarke. Focusing on the study of superconductivity and superconductor device physics, Van Harlingen has Logbook: single top production pioneered experimental techniques in low-temperature physics to investigate BY KURT REISSELMANN phase coherence and quantum phenomena in solid-state materials. His ground-breaking experimental n 1985, ten years before scientists at Fermilab discovered confirmation of the orbital d-wave Ithe top quark, Scott Willenbrock was a graduate student at pairing state of high-temperature the University of Texas at Austin. He and Duane Dicus were superconductors has led to major wondering how likely it would be for a particle collider such progress in superconductivity. as the Fermilab Tevatron to produce a single heavy quark. Current interests are determining the Willenbrock remembers that the eureka moment came pairing symmetry in unconventional when he was sitting in a UTexas shuttle bus on his way home. superconductors, fabricating Josephson There he realized that a subatomic process called “W-gluon pi-junctions for the design of solid- fusion” could lead to a single heavy quark. To outline the state qubits, developing scanning calculation, Willenbrock made this to-do list and included magnetic microscopy instruments, and the remark, “Could even be t quark!” characterizing transport in nanoscale “Back then we were thinking about a hypothetical superconducting structures. fourth generation of quarks [labeled U,D in the list],” says Van Harlingen is a Fellow of the Willenbrock, now a professor at the University of Illinois at American Physical Society, a member Urbana-Champaign. “Physicists had no idea how heavy the of the American Academy of Arts and [third-generation] top was, and we didn’t know whether Sciences and the National Academy of this calculation would be relevant to the top.” Sciences, and a recipient of the 1998 In 1995, the CDF and DZero experiments at Fermilab APS Oliver E. Buckley Prize in observed top quarks for the first time, produced in pairs via Condensed Matter Physics. the strong nuclear force. The particle was so heavy that Former heads of Physics are scientists began to search for single top quark production as Samuel W. Stratton (1890–1896), well.In December 2006, about twenty-one years after Dicus Albert P. Carman (1896–1929), and Willenbrock published their predictions [Phys. Rev. D 34, Production of heavy quarks from W-gluon fusion F. Wheeler Loomis (1929–1957), 155–161 (1986)—ed.], the DZero collaboration reported the Frederick Seitz (1957–1963), first evidence for single top production at the Tevatron. Gerald M. Almy (1963–1970), Ralph O. Simmons (1970–1986), Story courtesy Symmetry Magazine, Vol. 4, No. 1, January/February 2007. Reprinted with permission. Ansel C. Anderson (1986–1992), See www.symmetrymag.org/cms/?pid=1000431. David K. Campbell (1992–2000), and Jeremiah D. Sullivan (2000–2006). 2 PHYSICS ILLINOIS NEWS • 2007 NUMBER 1 Message from the Head a new dean in the College of Physics has ambitious plans also. Schrieffer in 1957. This is arguably Engineering, a new provost, a new One of my goals as head is to re-establish the single most significant academic chancellor, and a new president. the strong infrastructure and support for achievement ever to come out of the ver six We live in a new world—one that is the research programs of the department University of Illinois, and we will honor Omonths have rapidly changing and facing new threats that have always been a hallmark of our it by holding a major international passed since I to our economy and our security. program. Initiatives to strengthen the conference in Urbana this October, became the All of this will bring new challenges technical facilities, nucleate an Institute a great opportunity to celebrate work 10th head of the and new opportunities and in turn for Theoretical Condensed Matter that exemplifies the impact that our Department of requires and inspires new ideas. Physics, and partner with departments department has and can have when Physics. In that The campus has undergone an across the campus in STEM (science- we approach problems in the “Urbana time, I have extensive strategic planning exercise and technology-engineering-mathematics) style,” bringing strong theoretical and attended more is focusing emerging programs into the education are in motion. experimental expertise to bear on a meetings, signed challenges of information, sustainable Physics has a broad wavefunction single goal. more forms, and answered more emails energy, and human health care. At the that extends into a wide range of We are always appreciative of the than in the whole of my 25 years as a same time, initiatives are underway to interdisciplinary areas. We are interest and support from our Physics professor of physics here. But I have extend the impact of the University of committed to maintaining our core alumni and friends, and I hope that this also had the unique opportunity to learn Illinois on the international stage, by disciplinary strengths while expanding newsletter helps to give you a glimpse about the ambitions and accomplish- globalizing our research portfolio and our impact via exploration at the of the energy and quality of this ments of the talented faculty and staff launching a global online campus intersections of physics and other remarkable Department of Physics. that make up this great department. designed to educate a larger and more fields across campus, including Our message of creativity and This experience has reinforced what diverse student population. Such engineering, materials sciences, biological discovery that you help us spread I have long believed, that there is no initiatives are not without costs and sciences, environmental sciences, and the generous contributions you better place to do physics and no commitments by the already busy medical sciences, nanoscience, and make to the Department continue to warmer community in which to work faculty, so the University is information technology. drive and enhance our programs as than here in Urbana.
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