The research program consists of experimental studies of the radiative capture of polarized and unpolarized protons, and deuterons in light nuclei. The program is carried out at the Triangle Universities Nuclear Laboratory in collaboration with H. R. Weller of Duke. Experiments at TUNL have involved incident energies ranging from as high as 20 MeV to as low as 80 keV.The measurement of excitation functions, differential cross sections and analyzing powers in these reactions has been shown to be an effective way to probe the properties of the wave functions of these few-nucleon systems as well as properties of the nucleon-nucleon force. For example recent TUNL studies of polarized d + 3H, and d + 3He have shown that the fusion cross sections are enhanced by a factor of 16 by the tensor force acting in the scattering state. Recently we have utilized the 80 keV beam from the TUNL high-intensity polarized ion source to study the 7Li(p,g) reaction at astrophysical energies and have obtained results which could have a bearing on the solar neutrino problem. We have recently acquired a high-purity Germanium detector which has enabled us to carry out radiative capture experiments at astrophysical energies with unprecedented detector resolution.In addition to radiative capture experiments at TUNL we have recently carried out experiments on the 4He(g,d) reaction using the 200 MeV polarized photon beam from the LEGGS facility at Brookhaven National Laboratory. We are also involved with developing instrumentation for future experiments high energy electron accelerator facility at CEBAF.As an outgrowth of our research on few-nucleon systems, we carried out a compilation of nuclear data on the A=3 system at the request of the National Nuclear Data Center at Brookhaven National Laboratories. This task was completed during 1987 and was published in Nuclear Physics A in Spring 1988. We then began work on a compilation on the A = 4 system, and published this review in Nuclear Physics A in Fall 1992. In response to the recommendations in 1990 of the Panel on Basic Nuclear Data Compilations of the National Research Council our group at TUNL accepted responsibility for Nuclear Data Evaluationfor the A = 5 - 20 nuclei. We began work on the A = 16, 17 nuclei, and this review was completed and published in Nuclear Physics A in December 1993. We are now at work on a review of the A = 18 - 20 nuclei.
Areas of Interest
"Energy Levels of Light Nuclei A = 16, 17,"
D.R. Tilley, H.R. Weller, C.M. Cheves.
(1993). p. 1.
"Radiative Capture of Polarized Deuterons on 7Li,"
J. Z. Williams, G. J. Schmid, R. M. Chasteler, H. R. Weller, and D. R. Tilley.
(1993). p. 441.
"Observation of p-wave Capture Strength in the 2H(d,g)4He Reaction at Ed = 80-0 keV,"
L. H. Kramer, R. M. Chasteler, E. Hayward, R. M. Prior, D. R. Tilley and H. R. Weller.
(1993). p. 208.