Electromagnetic decay properties of high spin states in ${}_{43}{}^{91}{}_{}{}^{}\mathrm{Tc}_{48}^{}{}_{}{}^{}$

High spin states in the nucleus ${}_{}{}^{91}{}_{}{}^{}\mathrm{Tc}$ have been studied via the fusion evaporation reaction ${}_{}{}^{58}{}_{}{}^{}\mathrm{Ni}$ ${(}^{36}$Ar, 3p) ${}_{}{}^{91}{}_{}{}^{}\mathrm{Tc}$, at 149 MeV and 140 MeV beam energy. The OSIRIS spectrometer, an additional high purity Ge detector at 162°, and several particle detectors were used to measure γγ- and particle-γγ coincidences, directional correlations of oriented states and line shapes due to Doppler-shift attenuation. Lifetimes in the ${10}^{\mathrm{-}12}$–${10}^{\mathrm{-}9}$ s range were measured by the recoil distance Doppler-shift method. Some 110 transitions were placed into a level scheme comprising 51 levels reaching up to 12.2 MeV excitation energy and a possible spin I=49/2ħ. A large number of spin-paritly assignments and E2/M1 mixing ratios and lifetimes were deduced. This extensive data set is used for a detailed test of shell model calculations. They were performed with different sets of parameters, within either a restricted π(${\mathit{p}}_{1/2}$), π(${\mathit{g}}_{9/2}$), ν(${\mathit{p}}_{1/2}$), and ν(${\mathit{g}}_{9/2}$) configuration space or an enlarged configuration space including the π(${\mathit{p}}_{3/2}$) and π(${\mathit{f}}_{5/2}$) orbits.