Department of Physics at the University of Illinois at Urbana-Champaign

James E. Wiss

Professor of Physics

Professor James Wiss received his Ph.D. in Physics from the University of California, Berkeley, in 1977, after receiving a B.S. in physics from the University of Illinois in 1971. He joined the physics faculty at Illinois in 1979 as a visiting research assistant professor, and rose rapidly through the ranks, becoming a full professor in 1988.

Professor Wiss currently leads the Illinois group collaborating on the FOCUS experiment at Fermi National Accelerator Facility. FOCUS is a heavy-flavor photoproduction experiment located in the Wide Band Area of Fermilab . It is an upgraded version of its predecessor, E687 . The experiment accumulated data during the 1996-1997 fixed target run and has fully reconstructed more than one million charm particles using the 'golden mode' decays, D⁰ ® K^- p⁺, D⁰ ® K^- p⁺ p^- p⁺, and D⁺ ® K^- p⁺ p⁺.

Another active research area is the development of a prototype muon detector for the BTEV experiment at Fermilab. BTEV is designed to study the origin of CP violation in B Meson decays.

Research Areas: experimental high-energy physics, photoproduction of charmed mesons, precision study of the B meson.

Description of Current Research

Elementary Particle Experiment
The two main thrusts of high-energy physics research are to determine the form and strength of the fundamental interactions in nature and to determine the properties of the particles that enter into these interactions. The two main thrusts of elementary particle physics research are to determine the form and strength of the fundamental interactions in nature and to determine the properties of the particles that enter into these interactions. Our group presently works on experiments at Fermilab, Cornell University, and CERN. We participated in the discovery of the top quark and expect to observe time reversal symmetry violation in B-meson decays. In the future, we hope to observe the Higgs boson, thought to be responsible for the existence of mass.

High-Energy Photoproduction
We study charm particles produced by the interaction of high-energy photons on nuclear targets. We have reported on new measurements of charm lifetimes, photoproduction dynamics, hadronic and semileptonic decay, and excited state spectroscopy from our sample of 80,000 charm decays collected in the 1990/1991 run of Fermilab E687. Our next experiment, Focus, has collected over an order of magnitude more data with a significantly upgraded spectrometer. The Illinois group has made major contributions to the experimental software, hardware, and data analysis.

Selected Publications

Rosner, JL, et al. Observation of the h_c(¹P₁) state charmonium. Phys. Rev. Lett. 95, 102003 (2005).

Li, et al. Measurement of the branching fractions for J/y®l⁺l^-. Phys. Rev. D. 71, 111103-1-5 (2005).

Briere, et al. Observation of thirteen new exclusive multi-body hadronic decays of the y(2S). Phys. Rev. Lett. 95, 062001-1-5 (2005).

Adams, NE, et al. Observation of 1^-0^- final states from (2S) decays and e+e- annihilation. Phys. Rev. Lett. 94, 012005-1-5 (2005).

Adams, GS, et al. Measurement of the muonic branching fractions of the narrow Upsilon resonances. Phys. Rev. Lett. 94, 012001-1-5 (2005).

Honors and Awards

• Fellow, American Physical Society, 2000
• Fellow, Alfred P. Sloan Research Foundation, 1982

Other Pages

Personal Home Page

Preliminary Thoughts about BTeV Muon System