The 76Se Gamow–Teller strength distribution and its importance for stellar electron capture rates

Recent theoretical studies predicted that, due to nuclear correlations across the image shell gap, electron captures on nuclei with proton numbers image and neutron numbers image would not be strongly suppressed due to Pauli blocking of Gamow–Teller (GT) transitions. This prediction has recently been confirmed by the experimental determination of the single-particle occupation numbers in 76Se and by the measurement of the 76Se GT+ strength distribution. In this manuscript we derive such occupation numbers and GT+ distributions within large-scale shell model studies. Based on the same models, we calculate stellar electron capture rates and compare them to those obtained from the experimental GT+ data.