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Relation between the 16O(alpha,gamma)20Ne reaction and its reverse 20Ne(gamma,alpha)16O reaction in stars and in the laboratory

P. Mohr·C. Angulo·P. Descouvemont·H. Utsunomiya
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Abstract

The astrophysical reaction rates of the 16O(a,g)20Ne capture reaction and its inverse 20Ne(g,a)16O photodisintegration reaction are given by the sum of several narrow resonances and a small direct capture contribution at low temperatures. Although the thermal population of low lying excited states in 16O and 20Ne is extremely small, the first excited state in 20Ne plays a non-negligible role for the photodisintegration rate. Consequences for experiments with so-called quasi-thermal photon energy distributions are discussed.

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P. Mohr, C. Angulo, P. Descouvemont, H. Utsunomiya. 2005-06-05. Relation between the 16O(alpha,gamma)20Ne reaction and its reverse 20Ne(gamma,alpha)16O reaction in stars and in the laboratory. https://doi.org/10.1140/epja%2Fi2006-08-010-1

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