Spectroscopy of high spin states inBr73

Abstract
We report on the measurement of level energies, lifetimes, γ-ray intensities, and angular distributions in Br73, obtained in the reactions Ca40 (36Ar,3p) and Ca40 (40Ca,α3p). The g factor of the 241 keV isomeric state (τ=50 ns) was determined to be g=1.31(9) from the Larmor precession in an external magnetic field. The fully aligned members of a rotationally aligned g9/2 band were identified up to spin Iπ =(33/2+; the E2 transition strengths indicate a large prolate deformation decreasing from β2=0.37(4) to β2=0.33 at rotational frequency ħω≊0.45 MeV. The negative parity yrast bands with signatures α=±1/2 were established up to a probable spin of (37/2. The α=+1/2 yrast band shows a one quasiparticle to three quasiparticle band transition at the same frequency, probably associated with the alignment of two g9/2 protons. The structure of Br73, which is very similar to that of Br75, has been interpreted with the Strutinsky-Bogolyubov cranking and deformed configuration mixing models.