Theoretical reaction rates of the $^{12}$C($α$,$γ$)$^{16}$O reaction from the potential model

M. Katsuma

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arXiv · 1501.06250

Theoretical reaction rates of the $^{12}$C($α$,$γ$)$^{16}$O reaction from the potential model

M. Katsuma

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Abstract

The radiative capture cross sections of $^{12}$C($α$,$γ$)$^{16}$O and derived reaction rates are calculated from the direct capture potential model. The resulting $S$-factor at low energies is found to be dominated by $E$2 transition to the $^{16}$O ground state. The $E$1 and $E$2 $S$-factors at $E_{c.m.}=0.3$ MeV are $S_{E1}\approx3$ keV~b and $S_{E2}=150^{+41}_{-17}$ keV~b, respectively. The sum of the cascade transition through the excited state of $^{16}$O is $S_{\rm casc}= 18\pm4.5$ keV~b. The derived reaction rates at low temperatures seem to be concordant with those from the previous evaluation. For astrophysical applications, our reaction rates below $T_9=3$ are provided in an analytic expression.

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M. Katsuma. 2015-01-26. Theoretical reaction rates of the $^{12}$C($α$,$γ$)$^{16}$O reaction from the potential model. https://arxiv.org/abs/1501.06250

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