PROTON AND NEUTRON RESONANCES IN NITROGEN

Angular distributions and integrated cross sections have been measured for protons scattered elastically and inelastically from nitrogen. A broad peak, about 1 MeV wide, centered near 9 MeV, has been found in the elastic cross section without a corresponding rise in the cross section in any of the inelastic channels. The angular distribution suggests that this peak is a p-wave scattering. Broad peaks in inelastic channels (about 0.5 MeV wide) were observed near 10 MeV for protons leading to the second excited state of N14, and at 10.7 and 11.3 MeV for protons producing the fourth and sixth excited states. None of these peaks has a counterpart in the elastic scattering. They are probably caused by the production of intermediate states. Corresponding to the 9-MeV elastic proton resonance, we have found a broad resonance (0.4 MeV wide) in the elastic scattering of neutrons from nitrogen at 5.3 MeV. This resonance has a peak cross section of 0.5 b, which requires that the ratio of the neutron width to the total width be near unity. The nonelastic cross section does not show a resonance at this energy. © 1968 The American Physical Society.