Nuclear structure research is led by Robert Grzywacz, Kate Jones, and Lee Riedinger in experiment and Thomas Papenbrock, Lucas Platter, and Andrew Steiner, in theory. Both programs include the work of postdocs, graduate students, visitors, and research faculty. This research program has wide overlap with people and facilities in the Oak Ridge National Laboratory Physics Division. The strengths and mutual interests of the experimental and theoretical efforts have led to a combined program that is among the world's strongest university programs in nuclear structure physics. Even though research in this branch of nuclear physics has been conducted in some form for 40 years, the evolution of new ideas, directions, and tools has led to interesting new physics in recent years. Perhaps the two most visible aspects of nuclear structure research are the studies of nuclei at extremes of high angular momentum and at extremes of neutron/proton imbalance. These are exactly the two major areas of experimental and theoretical programs at UT.
In order to study nuclei far from stability, our faculty have in the past utilized isotope separators at Oak Ridge and CERN in Geneva, Switzerland, and more recently, the Fragment Mass Analyzer at Argonne National Laboratory, where UT has formed a collaboration to study the decay mechanism of proton radioactivity.
The other major thrust in UT's nuclear structure physics program is the study of nuclei at high angular momentum and in extremes of shape deformation. The discovery of superdeformation has led to intense studies of nuclear collective modes with ever increasing arrays of gamma-ray detectors. Both our experimental and theoretical groups are extremely active in high-spin physics. At present, the world's best detector for nuclei in extreme spin modes is called GAMMASPHERE, composed of 110 Compton-suppressed Ge counters. This detector is stationed at the Lawrence Berkeley National Laboratory and is a prime source of experimental data for the UT research group.
Experimental Nuclear Astrophysics
The experimental nuclear astrophysics group performs experiments in Earth-based laboratories to try to understand the nuclear reactions that occur in stars. This information is essential to unraveling observational data such as light curves and spectra in order to better understand the conditions for nucleosynthesis.