Several QRPA method calculations of the Gamow–Teller strength distributions in $$^{62{-}72}$$Ge

Abstract

Studies of exotic nuclei are currently one of the most prolific in nuclear physics. Weak rates in germanium isotopes have a fundamental role in the dynamics of supernovae. Electron capture and beta-decay of germanium isotopes, specified by Gamow–Teller transitions, importantly modify the lepton fraction of the stellar matter. In this study, Gamow–Teller Transitions (GT) for $$^{62{-}72}$$ Ge are calculated using QRPA methods. The GT strength distributions are calculated using eight different QRPA models. QRPA models, namely single quasi-particle (sqp), Pyatov method (PM) and the schematic model (SM), are further divided into four subcategories. Using these models, Gamow–Teller distribution, total GT strengths along electron capture direction ( $$\sum $$ B(GT) $$_+$$ ) and Ikeda sum rule are calculated. The results of sqp, PM, and SM are also compared with previous theoretical calculations and measured strength distributions wherever available. It is expected that this study of GT properties would gain favor and may help to a better understanding of the presupernova evolution of massive stars.