High spin structure ofBr75and the (N,Z) dependence of the nuclear deformation in the Br region

High spin states of ${}_{}{}^{75}{}_{}{}^{}\mathrm{Br}$ were studied through the ${}_{}{}^{62}{}_{}{}^{}\mathrm{Ni} ({}_{}{}^{16}{}_{}{}^{}\mathrm{O},2np)$ reaction. A positive and a negative parity band were established up to spin (25/2). A new low-lying isomeric (9/$2^{+}$) state ($T_{\frac{1}{2}}=39\mathrm{}\pm 4$ ns) at 220.6 keV excitation energy, most likely of $\tilde{\pi }{g}_{\frac{9}{2}}$ parentage, was found. The structure was interpreted in the light of the one quasiparticle plus rotor model concluding that the quadrupole deformation is largest for ${}_{}{}^{75}{}_{}{}^{}\mathrm{Br}$ compared to all other known odd Br isotopes.