K. Kar et al., HALF-LIVES AND PRESUPERNOVA WEAK INTERACTION RATES FOR NUCLEI AWAY FROM THE STABILITY LINE, Journal of physics. G, Nuclear and particle physics, 24(8), 1998, pp. 1641-1645
A detailed model for the calculation of B-decay rates of the fp shell
nuclei for situations prevailing in presupernova and collapse phases o
f evolution of the core of massive stars leading to supernova explosio
n has been extended for electron-capture rates. It can also be used to
determine the half-lives of neutron-rich nuclei in the fp/fpg shell.
The model uses an averaged Gamow-Teller (GT) strength function, but it
can also use the experimental log ft values and GT strength function
from (n,p) reaction studies wherever available. The calculated rate in
cludes contributions from each of the low-lying excited states of the
mother including some specific resonant states ('back resonance') havi
ng large GT matrix elements.