C13(p,γ)N14Reaction and the 9.17-, 7.03-, and 6.44-MeV States inN14

Abstract

A re-examination of the $\ensuremath{\gamma}$-ray decay of the 9.17-MeV state in ${\mathrm{N}}^{14}$, reached at the 1.75-MeV resonance in the ${\mathrm{C}}^{13}(p,\ensuremath{\gamma}){\mathrm{N}}^{14}$ reaction, has confirmed the shell-model assignments previously given to that state and the 7.03-MeV state. The observation of a weak transition to the 2.31-MeV state supports the positive parity assignment of the 9.17-MeV state. Angular distribution and correlation measurements indicate an amplitude ratio of $f$ wave to $p$ wave in the formation of the compound state of -0.70\ifmmode\pm\else\textpm\fi{}0.26 and $\frac{E2}{M1}$ amplitude ratios of -0.005\ifmmode\pm\else\textpm\fi{}0.020 and -0.6\ifmmode\pm\else\textpm\fi{}0.1 for the 9.17 \ensuremath{\rightarrow} ground-state and 7.03 \ensuremath{\rightarrow} ground-state transitions, respectively. A slight preference for a positive parity assignment for the 6.44-MeV state is found. The results, in general, are in good agreement with the calculations of Warburton and Pinkston. The alternative shell-model configurations suggested by them for the 6.44-MeV state are examined, but existing data are found to be inconclusive.