Spin-isospin excitations in 13N have been studied by means of the (3He,t) and (3He,tp) reactions at a bombarding energy of E(3He)=450 MeV. The zero-degree (3He,t) spectrum is found to be similar to those from the (p,n) reactions at intermediate energies, suggesting a simple direct reaction mechanism at E(3He) =450 MeV. The Gamow-Teller (GT) states with Jπ=1/2- and 3/2 - have been strongly excited at θlab=0°. The angular distribution of cross sections for the 13C( 3He,t)13N reaction and the elastic 3He scattering off 13C were obtained at θlab=0° - 17° and at θlab=2° - 22°, respectively. The obtained experimental results were compared with calculations performed in distorted-wave Born approximation. Microscopic structures of the states in 13N have further been studied by observing decay protons in coincidence with high-energy tritons measured at θlab=0°. The branching ratios for proton decay from the GT states in 13N to the final low-lying T=0 states in 12C were obtained. The wave functions of the excited states in 13N are discussed on the basis of obtained experimental data and relevant theoretical calculations.
ASJC Scopus subject areas
- Nuclear and High Energy Physics