Microscopic calculations of stellar weak interaction rates and energy losses for fp- and fpg-shell nuclei

摘要

Nuclear weak interaction rates for fp- and fpg-shell nuclei in stellar matter and the associated energy losses are calculated using a modified form of proton-neutron quasiparticle random phase approximation model with separable Gamow-Teller forces. The stellar weak rates are calculated over a wide range of densities (10 less than or equal to rho Y-e (g cm(-3)) less than or equal to 10(11)) and temperatures (10(7) less than or equal to T (K) less than or equal to 30 x 10(9)). We also calculate the probability of particle emission processes in stellar environment. We present an extensive compilation of weak interaction rates in stellar matter calculated over a wide temperature-density grid and over a large mass range. The calculated capture and decay rates take into consideration the latest compilations of experimental energy levels and ft values. This paper is a follow up of our calculations introduced earlier [Eur. Phys. J. A 5 (1999) 337]. We have calculated stellar weak interaction rates for a total of 650 nuclei in the mass range A = 40-100. These also include many important neutron-rich nuclei which play an important role in the evolution process of stellar collapse. (C) 2004 Elsevier Inc. All rights reserved.