Low energy proton capture in light nuclei. Progress report, September 1, 1993--June 8, 1994

Radiative capture reactions with light nuclei are of special interest in nuclear astrophysics because of their importance in the formation of the various elements. In many cases a simple direct-capture model that considers only the electromagnetic interaction is sufficient to reproduce experimental results. A direct-semidirect process may be used in which the transition amplitude is the sum of a direct term and another term representing the excitation of the target nucleus into a collective state. In cases where these approaches are not sufficient, the relative simplicity of nuclear systems with small numbers of fundamental particles allows microscopic calculations of measurable quantities from nucleon-nucleon potentials, using the multichannel resonating group model or, in some cases, Faddeev calculations. In the summer of 1990, the PI began a collaboration with Professor Henry Weller`s group at the Triangle Universities Nuclear Laboratory (TUNL). Weller`s group has studied radiative capture reactions with polarized beams at TUNL for over a decade, developing considerable expertise in the detection of high energy gamma rays and for the analysis of the measurements. The PI has been involved in the development of a new series of experiments at beam energies below 100 keV, using the positive beam directly from the high intensity atomic beam polarized ion source. This work is the topic of the present grant, which began September 1, 1993. The main activity in the grant occurs during the summer months. Since this is the first year of the grant, most of that activity will be during the upcoming summer months. The PI will travel to TUNL in mid-June and will spend most of his time from then through August either at TUNL or working on data reduction and other calculations at West Georgia College. The PI is moving from West Georgia College (WGC) to North Georgia College (NGC) in September, 1994. He will be Professor and Chair of Physics there as he has been at WGC