Comparison of polarization and analyzing power for the 15N(p, n)15O reaction

The analyzing power Ay(θ) and polarization P^y(θ) for the ¹⁵N(p, n0)¹⁵O reaction have been measured for Ep = 4.5-11.3 MeV. The values of the two observables are nearly the same above 11 MeV, where a "quasi-elastic" view of the (p, n) reaction to the analog state should be applicable. Below 10 MeV, however, large spin-flip amplitudes and isospin-mixing ratios provide the two major conditions needed to obtain P^y(θ) ≠ Ay(θ), and dramatic differences between the two observables are observed. The size of the differences and their dependence on energy are similar to the results predicted by shell-model calculations. The P^y(θ) and Ay(θ) measurements have been combined with existing cross-section data to provide information about spin-flip processes. We also comment on the connection between comparisons of P^y (θ) and Ay (θ) in charge-symmetric (p, n) reactions and the recent controversial measurements of a difference between the values of P^y(θ) for a reaction and Ay(θ) for the inverse reaction. © 1983.

Duke Scholars

Author Werner Tornow Physics