Abstract:
High-spin states in the 73Br nucleus have been populated via the 50Cr(28Si, αp)73Br fusion evaporation
reaction with a beam energy of 90 MeV. The deexciting gamma rays were detected using the Indian National
Gamma Array (INGA). Using the γ -γ coincidence technique, two new bands and eight new interconnecting
transitions have been added. The strong interconnecting E1 transitions, between positive and negative parity
bands, ensure the existence of octupole correlations at low spin. Line shapes have been observed for 17
transitions, which were analyzed by the Doppler-shift attenuation method to determine the lifetime of excited
states of the yrast negative parity band and its signature partner band along with the positive parity band. The
deduced transitional quadrupole moments Qt for the ground state band decrease with increasing spin, with their
values ranging from 2.88 to 1.00 eb. A similar trend in the quadrupole moment has also been observed for the
signature partner as well as for the positive parity band. This decrease in Qt with increasing spin for these bands
is interpreted in terms of the cranked Nilsson-Strutinsky model and total Routhian surface calculations, which
indicate possible band termination at higher spin.
