Isotope dependence of widths of hole analog states

The isotope dependence of the widths of the hole analog states is studied for the Zr, Mo and Sn isotopes. In order to calculate the proton escape widths, we propose a microscopic model, in which the coupling of a neutron hole state to the isobaric analog state of the core is considered. It is found that the proton escape widths carry the observed isotope dependence of the widths of the hole analog states and that the isotope dependence of the proton escape widths is caused by two effects: the isotope dependence of the maximum available energy for a decaying proton, and that of the occupation probabilities of the excess neutron orbits in the parent state.