The level scheme of91Tc and theβ decay of91Ru(9/2+)

The level scheme of⁹¹Tc has been studied by means of in-beamγ-ray spectroscopy in the irradiations of⁵⁸Ni and⁵⁴Fe targets by⁴⁰Ca beams from the Munich MP tandem and the heavy ion post accelerator. A large number of positive as well as of negative parity yrast-levels with excitation energies up to 8 MeV has been established. The level scheme of⁹¹Tc has been compared with shell model claculations and a good agreement for all identified levels has been found. In parallel investigations of the residual activities of the reaction⁴⁰Ca→⁵⁴Fe, theβ decay of the (9/2⁺ ground) state of⁹¹Ru has been investigated. Aβ decay scheme of⁹¹Ru(9/2⁺) has been established. The half-life of⁹¹Ru(9/2⁺) has been measured to be 9±1 s.