Experimental investigation of high-spin states in Zr 90

Abstract

High-spin states of Zr90 have been investigated using the heavy-ion fusion-evaporation reaction Se82(C13,5n) at a beam energy of 60 MeV. Excited levels of Zr90 have been observed up to an excitation energy of ≈13 MeV and a spin of ≈20 with the addition of thirty-Two new γ-ray transitions to the proposed level scheme. Structures of both the positive-and negative-parity states up to the highest observed spin have been interpreted with shell-model calculations using the GWBXG interaction and a Ni68 core. Calculations suggest the role of neutron excitations across the N=50 shell gap for states with greater than 7 MeV excitation energy. High-spin states in these bands are interpreted to be generated by the recoupling of stretched proton and neutron configurations. © 2022 American Physical Society.