Excitation of 1p-1h stretched states with the (p,n) reaction as a test of shell-model calculations

The medium-energy (p,n) reaction at large-momentum transfer preferentially excites 1p-1h stretched states. Both 0ℎω and 1ℎω excitations are observed. These states have been observed in many nuclei and provide relatively simple tests of structure calculations. Normalization factors required for DWIA calculations which assume the simple shell model are observed to be 0.6 ± 0.1 universally for 0ℎω excitations. Normalization factors required for 1ℎω excitations are almost always smaller; large-basis shell-model calculations are sometimes able to account for these normalization factors