γ-ray decay from neutron-bound and unbound states in Mo 95 and a novel technique for spin determination

Abstract

The emission of γ rays from neutron-bound and neutron-unbound states in 95 Mo , populated in the 94 Mo ( d , p ) reaction, has been investigated. Charged particles and γ radiation were detected with arrays of annular silicon and Clover-type high-purity Germanium detectors, respectively. Utilizing p− γ and p− γ − γ coincidences, the 95 Mo level scheme was greatly enhanced with 102 new transitions and 43 new states. It agrees well with shell model calculations for excitation energies below ≈ 2 MeV. From p− γ coincidence data, a new method for the determination of spins of discrete levels is proposed. The method exploits the suppression of high-angular momentum neutron emission from levels with high spins populated in the (d,p) reaction above the neutron separation energy. Spins for almost all 95 Mo levels below 2 MeV (and for a few levels above) have been determined with this method.