Direct Reactions with Exotic Beams and Polarized Lithium Beams

• Other Authors: Roeder, Brian T. (authoraut)
• Format: Others
• Language: English; English
• Published: Florida State University
• Subjects: Physics
• Online Access: http://purl.flvc.org/fsu/fd/FSU_migr_etd-1941

In the first two chapters of this dissertation, the total cross sections for 38 different reaction products produced in the interaction of 48Ca, 40S and 42S beams at energies around 100 MeV/nucleon with a liquid deuterium target are reported. The cross sections for the 48Ca+d products are compared to those with 48Ca incident on the commonly used fragmentation targets 9Be and 181Ta, and also to global calculations for fragmentation reaction cross sections based on the EPAX parameterization performed with the program LISE. The sizes of the measured reaction cross sections for the deuterium target were comparable to the cross sections measured on the heavier targets indicating that both nucleon addition and removal from a deuterium target can be carried out for comparative "stripping" and "pickup" reaction studies. It was also found that the charge exchange cross sections were large enough so that it should be possible to obtain nuclear structure information from these reactions. Calculations using the Johnson-Soper adiabatic model and Eikonal nucleon knockout theory were performed to study the reaction mechanisms for the "stripping" and "pickup" reactions studied in the experiment. It was found that the magnitude of the cross sections for both the single nucleon "stripping" and single nucleon "pickup" reactions were consistent with the assumption that they proceeded as direct, single step reactions. In the third chapter of this dissertation, the recent upgrade to the Florida State University Optically Pumped Polarized Lithium Ion Source (OPPLIS) is summarized. A new laser system was installed, and the laser optics were modified to increase the laser power available for optically pumping the lithium atomic beam from about 40 mW to nearly 200 mW. This improvement, along with proper alignment of the laser beam divergence to the atomic beam divergence, increased the vector polarization t10 of the beam on-target from about 40% to about 60%. === A Dissertation Submitted to the Department of Physics in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy. === Summer Semester, 2006. === May 12, 2006. === Direct Reactions, Exotic Beams, Liquid Deuterium Target, Polarized Lithium Beam === Includes bibliographical references. === Kirby Kemper, Professor Directing Dissertation; Brooks Keel, Outside Committee Member; Ingo Wiedenhoever, Committee Member; Jorge Piekarewicz, Committee Member; Edmund Myers, Committee Member.