High-resolution study of Gamow-Teller transitions in the Ti-47(He-3, t)V-47 reaction

Given the importance of Gamow-Teller (GT) transitions in nuclear structure and astrophysical nuclear processes, we have studied T z =+ 3 / 2 →+ 1 / 2, GT transitions starting from the 47 Ti nucleus in the ( 3 He ,t ) charge-exchange reaction at 0 ◦ and at an intermediate incident energy of 140 MeV / nucleon. The experiments were carried out at the Research Center for Nuclear Physics (RCNP), Osaka, using the high-resolution facility with a high-dispersion beam line and the Grand-Raiden spectrometer. With an energy resolution of 20 keV, individual GT transitions were observed and GT strength was derived for each state populated up to an excitation energy ( E x ) of 12.5 MeV. The GT strength was widely distributed from low excitation energy up to 12.5 MeV, where we had to stop the analysis because of the high level density. The distribution of the GT strengths was compared with the results of shell model calculations using the GXPF1 interaction. The calculations could reproduce the experimental GT distributions well. The GT transitions from the ground state of 47 Ti and the M 1 transitions from the isobaric analog state in 47 V to the same low-lying states in 47 V are analogous. It was found that the ratios of GT transition strengths to the ground state, the 0.088-MeV state, and the 0.146-MeV state are similar to the ratios of the strengths of the analogous M 1 transitions from the isobaric analog state (IAS) to these states. The measured distribution of the GT strengths was also compared with those starting from the T z =+ 3 / 2 nucleus 41 Ktothe T z =+ 1 / 2 nucleus 41 Ca.status: publishe