Electromagnetic properties of states in 92Mo from the 92Mo(p, p′γ) reaction

Abstract

Levels in 92Mo were studied through the 92Mo(p, p′γ) reaction at incident proton energies E p = 7.0, 7.6 and 8.5 MeV. Singles γ-ray spectra were obtained with a Ge(Li) detector at angles of observation θ γ = 0°, 30°, 55°, 70°, 90° and 125°. Level and transition energies were extracted from the θ γ = 90° spectra with an accuracy better than ± 0.5 keV. Branching ratios were extracted from the θ γ = 55° spectra. For transitions demonstrating an energy shift with respect to the angle of observation, the corresponding lifetime of the state was determined through the Doppler shift attenuation method. The analysis of angular distributions yielded multipole mixing ratios and J π values for several states. The experimental information obtained in this work was employed to calculate reduced transition probabilities. The properties of low-lying states in 92Mo strongly indicate that this nucleus may be described in the framework of the shell model by considering simple configurations of four protons occupying the p 1 2 and g 9 2 orbitals outside an inert 88Sr core.