Effective decay rates of nuclei in astrophysical environments*

Abstract Nuclear β -decay plays a pivotal role at various stages of stellar evolution. However, the effective decay rates of nuclei in astrophysical environments may differ significantly from their laboratory values. This paper presents a detailed methodology for calculating nuclear half-life under the influence of temperature, electron density, ionization, and incomplete thermal equilibrium. We analyze the impact of astrophysical conditions on the β -decay of 26 Al, 59 Fe, 79 Se, and 205 Pb, revealing substantial variations in their effective half-lives within stellar environments. These changes lead to significant differences in nucleosynthetic yields, underscoring the critical importance of accounting for environmental effects when modeling nuclear decay rates.