Abstract
The odd-proton nuclei 127Pr and 131Pm have been investigated using the 96Ru(35Cl,2p2n) and 96Ru(40Ca,αp)/96Ru(39K,2p2n) reactions, respectively, at beam energies of 164, 180, and 186 MeV. States belonging to the yrast bands of 127Pr and 131Pm, which are interpreted as being based upon the h11/2 [541]3/2- proton configuration, have been observed from the 11/2- band head to spin 47/2-. The properties of these two new structures are observed to be different to those of similar configurations in the heavier odd mass isotopes. The systematics of the band crossings in the πh11/2 bands of the odd mass Pr and Pm isotopes are discussed and compared with extended total Routhian surface calculations.