Gamow-Teller strength distributions infp-shell nuclei

Abstract

We use the shell model Monte Carlo method to calculate complete $0f1p$-shell response functions for Gamow-Teller (GT) operators and obtain the corresponding strength distributions using a maximum entropy technique. The approach is validated against direct diagonalization for ${}^{48}$Ti. Calculated GT strength distributions agree well with data from $\mathrm{}(n,p)\mathrm{}$ and $\mathrm{}(p,n)\mathrm{}$ reactions for nuclei with $A=48\mathrm{}$–64. We also calculate the temperature evolution of the GT${}_{+}$ distributions for representative nuclei and find that the GT${}_{+}$ distributions broaden and the centroids shift to lower energies with increasing temperature.