Structure of isobaric analog states in 91Nb populated by the 90Zr(a,t) reaction

Decay via proton emission of isobaric analog states (IAS's) in $^{91}{Nb}$ was studied using the $^{90}{Zr}(\alpha,t)$ reaction at $E_\alpha$=180 MeV. This study provides information about the damping mechanism of these states. Decay to the ground state and low-lying phonon states in $^{90}{Zr}$ was observed. The experimental data are compared with theoretical predictions wherein the IAS `single-particle' proton escape widths are calculated in a continuum RPA approach. The branching ratios for decay to the phonon states are explained using a simple model.Comment: 3 figures. submitted to Phys. Lett.

Structure of 11/2−^- analog states in 91^{91}Nb populated by the 90^{90}Zr (α\alpha,t) reaction

Decay via proton emission of isobaric analog states (IAS's) in $^{91}{Nb}$ was studied using the $^{90}{Zr}(\alpha,t)$ reaction at $E_\alpha$=180 MeV. This study provides information about the damping mechanism of these states. Decay to the ground state and low-lying phonon states in $^{90}{Zr}$ was observed. The experimental data are compared with theoretical predictions wherein the IAS `single-particle' proton escape widths are calculated in a continuum RPA approach. The branching ratios for decay to the phonon states are explained using a simple model

Damping mechanisms of high-lying single-particle states in 91^{91}Nb

Decay by proton emission from high-lying states in 91Nb, populated in the 90Zr(alpha,t) reaction at Ealpha=180 MeV, has been investigated. Decay to the ground state and semidirect decay to the low-lying (2+,5-, and 3-) phonon states in 90Zr were observed. It was found that these phonon states play an important role in the damping process of the single-particle states. An optical-model coupled-channel approach was used successfully to describe the direct and semidirect parts of the decay