Stellar enhancement factors in a parity dependent approach

The s-process takes place in stellar environments with temperatures between 8 to 100 keV. In such a plasma the nuclei follow a Maxwell-Boltzmann distribution. Reactions between nucei are characterized by a reaction rate that depends on the temperature of the stellar environment. Reaction rates based on experimental cross sections 〈σv〉 lab do not account for the thermal excitation of the nuclei. This effect can be included by the so-called stellar enhancement factors (SEF), defined as the theoretical ratio of the stellar reaction rate 〈σv〉∗, that describes the reaction in a stellar plasma including contributions of excited states, and the laboratory reaction rate 〈σv〉lab, that describes the reaction with the nucleus being in its groundstate. In our work we calculated the SEF for (n,γ)-reactions of all s-process nuclei in a statistical model with parity dependent level densities.