6533b833fe1ef96bd129c106

RESEARCH PRODUCT

New calculations of grossβ-decay properties for astrophysical applications: Speeding-up the classicalrprocess

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Recent compilations of experimental gross $\ensuremath{\beta}$-decay properties, i.e., half-lives ${(T}_{1/2})$ and neutron-emission probabilities ${(P}_{\mathrm{n}}),$ are compared to improved global macroscopic-microscopic model predictions. The model combines calculations within the quasiparticle (QP) random-phase approximation for the Gamow-Teller (GT) part with an empirical spreading of the QP strength and the gross theory for the first-forbidden part of ${\ensuremath{\beta}}^{\ensuremath{-}}$ decay. Nuclear masses are either taken from the 1995 data compilation of Audi et al., when available, otherwise from the finite-range droplet model. Especially for spherical and neutron-(sub-)magic isotopes a considerable improvement compared to our earlier predictions for pure GT decay (ADNDT, 1997) is observed. ${T}_{1/2}$ and ${P}_{\mathrm{n}}$ values up to the neutron drip line have been used in r-process calculations within the classical ``waiting-point'' approximation. With the new nuclear-physics input, a considerable speeding-up of the r-matter flow is observed, in particular at those r-abundance peaks which are related to magic neutron-shell closures.