Using fast Neutrons to Explore Nuclear Structure

The basic research program of the nuclear structure group at the University of Kentucky (UK) focuses on timely, related topics in nuclear spectroscopy, neutron-induced reactions, neutron-emitting reactions, and neutron scattering. Most of this work will utilize fast neutrons produced at the University's accelerator laboratory and the "(-ray and neutron detection capabilities developed in this laboratory. Collaborative research with colleagues from other institutions is emphasized. Nuclear structure studies at UK are primarily oriented toward exploring multiphonon vibrational excitations of the quadrupole and octupole types in nearly spherical nuclei, examining transition rates of decays from collective excitations, defining the roles of protons and neutrons in collective modes, and understanding nuclear shell structure and the nature of nuclear shape transitions. Lifetime measurements with the Doppler-shift method and "(-"(coincidence measurements, for which the methodology has been developed over many years in our laboratory, provide crucial information in many of these investigations. Studies of isospin symmetry with helium-ion-induced reactions define a complementary research direction for our program. Carefully selected projects that are particularly appropriate to the capabilities and facilities of the UK accelerator laboratory will be pursued. Education at the undergraduate, graduate, and post-graduate levels continues to be an integral part of all activities in our laboratory and, of course, graduates of this program contribute to the supply of trained nuclear scientists. Providing a supportive professional experience for students in nuclear science at the University of Kentucky is an ongoing, vital component of our program, and these students enthusiastically participate in national and international scientific meetings and the activities of professional societies. Female students form an unusually large component of our research group. For many years, the research facilities of our laboratory have been made available to students and faculty from non-doctoral-granting institutions, as well as other research universities and national laboratories, and research collaborations have been encouraged. Colleagues at UK and from other institutions frequently take advantage of our laboratory facilities to obtain information that may be crucial for the design of experiments at larger facilities, e.g., TRIUMF, LANSCE, and JLAB, or in other areas of physics. Research performed in our laboratory is directly applicable to problems of national interest and homeland security. These applications are well represented by the activities of government and industrial partners who utilize our accelerator and research equipment. For example, recent collaborative studies with industry have led to improved neutron-detection-based methods for the inspection of luggage for explosives and illegal drugs. In addition, we maintain the capacity to perform elemental analysis using techniques such as particle-induced X-ray emission (PIXE), particle-induced "(-ray emission (PIGE), and Rutherford backscattering (RBS) analysis. Our facilities have been utilized by a local elemental analysis company for a variety of applications. In each case, the unique capabilities were important considerations in the selection of our laboratory for this work.