{sup 7}Li({rvec p},{gamma}){sup 8} Be reaction at E{sub p}=80{endash}0 keV
- Department of Physics, Duke University, Durham, North Carolina 27708 (United States)
- Triangle Universities Nuclear Laboratory, Durham, North Carolina 27708-0308 (United States)
- North Georgia College and State University, Dahlonega, Georgia 30597 (United States)
- North Carolina State University, Raleigh, North Carolina 27695 (United States)
The {sup 7}Li({rvec p},{gamma}){sup 8}Be reaction has been studied in the laboratory energy range E{sub p}=80{endash}0 keV. The vector analyzing powers A{sub y}({theta}) and the angular distributions of the cross section d{sigma}/d{Omega}({theta}) for capture to the ground, first-, and third-excited states are reported. Additionally, the absolute cross section {sigma}{sub T}(E) and (equivalently) the astrophysical S factor S(E) have been measured for capture to the third-excited state. Calculations have been performed for all three transitions using the direct capture model to which the known nearby M1 resonances were added. While they predict the angular distribution observed for the cross section and analyzing power in the case of both the first and third-excited states of {sup 8}Be, they do not reproduce those for the ground state. These calculations predict negligible M1 strength below 80 keV for capture to the third-excited state (2{sup +}, T=0+1, 16.6 MeV), and we therefore conclude that the extrapolation of the astrophysical S factor for the {sup 7}Be(p,{gamma}){sup 8}B reaction, which has been performed previously by assuming pure E1 capture, is valid with regard to the neglect of any significant p-wave capture strength. {copyright} {ital 1997} {ital The American Physical Society}
- DOE Contract Number:
- FG02-91ER40619; FG05-95ER40902
- OSTI ID:
- 664490
- Journal Information:
- Physical Review, C, Journal Name: Physical Review, C Journal Issue: 3 Vol. 56; ISSN PRVCAN; ISSN 0556-2813
- Country of Publication:
- United States
- Language:
- English
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