Alignments in the Odd-Proton Actinides Np-237 and Am-241

High spin states in Np-237 and Am-241 have been studied with the "unsafe" Coulomb excitation technique. In each nucleus, signature partner rotational bands built on the [523]5/2(-) and [642]5/2(+) orbitals of respective h(9/2) and i(13/2) parentage have been delineated. An additional pair of bands based on the [521]3/2(-) (f(7/2)) state was also observed in Am-241. New information on the even-even Pu-236 and Cm-242 transfer products is also presented. From the present data, the role of i(13/2) protons in generating angular momentum in the even-even nuclei of the region is documented. A satisfactory description of the evolution of the rotational sequences with spin is achieved within the framework of the cranked shell model. Nevertheless, when combined with information on odd-neutron nuclei available from elsewhere, the data highlight significant shortcomings of the available theoretical predictions.