Spectroscopy of 1 9 3 , 1 9 5 , 1 9 7 Po

Excited states built on the ${13/2}^{+}$ isomers of the odd-mass ${}^{193,195,197}$Po isotopes have been observed via in-beam $\ensuremath{\gamma}$-ray spectroscopy. The $\ensuremath{\alpha}$ radioactivity of these isotopes has been used to tag $\ensuremath{\gamma}$-ray transitions following the ${}^{A}$Er+164 MeV ${}^{32}$S reactions, where $A=164$, 166, 167, 168, and 170. Prompt $\ensuremath{\gamma}$ radiation was measured by ten Compton-suppressed Ge detectors at the target position and the Fragment Mass Analyzer was used to select evaporation residues. The results are compared with the first excited states of the heavier odd-mass polonium isotopes and of the even-mass cores.