The ratio of S-factors for (p,γ) reactions on ^12C and ^13C at astrophysically relevant energies
Abstract
We have measured the ratio of the (p,γ) reaction yields on ^12C and ^13C with low energy protons (Ep <= 160 keV). At equilibrium in the CNO cycle, the abundances of ^12C and ^13C are inversely proportional to the (p,γ) reaction rates on these nuclei. The (p,γ) experiments were performed by stopping a 60 μA proton beam in a frozen mixture of ^12C and ^13C benzenes. The γ-rays from both reactions were detected by a 128% HPGe detector. The preliminary experimentally determined ratio of S-factors for ^12C(p,γ)/^13C(p,γ) is 0.25 ± 0.05 at an effective proton energy of 143 keV. A detailed description of the procedures used to determine this ratio and its error will be presented. The results will be compared to the ratio obtained from previous direct measurements of the two cross sections.
- Publication:
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APS April Meeting Abstracts
- Pub Date:
- April 2001
- Bibcode:
- 2001APS..APR.B8001N