Cross sections for the C12(p)C12 and N14(p)N14 reactions have been measured at Ep=122 MeV. Scattered protons were momentum analyzed in a dispersion-matched magnetic spectrograph and detected in a helical-cathode position-sensitive proportional counter. Transitions to states in C12 at 4.44 MeV (2+,T=0), 12.71 MeV (1+,0), 15.11 MeV (1+,1), 16.11 MeV (2+,1), and in N14 at 2.31 MeV (0+,1) and 3.95 MeV (1+,0), are very useful for studying the spin-isospin dependence of the effective two-nucleon interaction. Cross sections for these states from the present experiment and from earlier measurements at 185 MeV have been analyzed in the distorted-wave impulse approximation. Simultaneous consideration of (e) data for the same transitions helped to disentangle some nuclear-structure and reaction-mechanism effects. The distorted-wave impulse approximation provides a good description of those transitions in C12 mediated predominantly by the S=T=1 part of the effective interaction and also gives a reasonable description of the S=T=0 transitions in both nuclei. The mechanisms for excitation of the 12.71-MeV state in C12 (S=1, T=0) and the 2.31-MeV state in N14 (S=1, T=1) remain a puzzle. NUCLEAR REACTIONS C12, N14(p,p), (p), E=122 MeV; measured (Ep); resolution 100 keV;=6-60°. C12 2+states deduced 2 DWIA analysis; microscopic effective interaction with L tensor, and exchange terms.
ASJC Scopus subject areas
- Nuclear and High Energy Physics