LABORATORI NAZIONALI DEL SUD
High-resolution study of Gamow-Teller transitions in the 47Ti(3He,t)47V reaction E. Ganioðlu1, H. Fujita2, Y. Fujita2 , T. Adachi3, A. Algora4, M. Csatlos5, J. Deaven6, E. Estevez4,C. Guess6, J. Gulyas5, K. Hatanaka3, K. Hirota3, M. Honma,7 D. Ishikawa3, A. Krasznahorkay5, H. Matsubara3,R. Meharchand6, F. Molina4, H. Okamura3, H.J. Ong3, T. Otsuka,8 G. Perdikakis6, B. Rubio4, C. Scholl9, Y. Shimbara,10 G. Susoy1, T. Suzuki3, A. Tamii3, J. Thies8, R.G.T. Zegers6, J. Zenihiro3 1Department of Physics, Istanbul University, Istanbul 34134, Turkey 2Department of Physics, Osaka University, Toyonaka, Osaka 560-0043, Japan 3Research Center for Nuclear Physics, Osaka University, Ibaraki, Osaka 567-0047, Japan 4Instituto de Fßsica Corpuscular, CSIC-Universidad de Valencia, E-46071 Valencia, Spain 5Institute of Nuclear Research of the Hungarian Academy of Sciences P.O.Box 51, H-4001 Debrecen, Hungary 6NSCL, Michigan State University, East Lansing, Michigan 48824-1321, USA 7 Center for Mathematical Science, University of Aizu, Aizu-Wakamatsu, Fukushima 965-8580, Japan 8 Department of Physics, University of Tokyo, Hongo, Bunkyo, Tokyo 113-0033, Japan 9Institut für Kernphysik, Universität zu Köln, 50937 Köln, Germany 10Graduate School of Science & Technology, Niigata University, Nishi, Niigata, 950-2181, Japan 11Institut für Kernphysik, Westfälische Wilhelms-Universität, D-48149 Münster, Germany Gamow-Teller (GT) transitions play key roles in the studies of nuclear structure as well as astrophysical processes. In the pf-shell nuclei, they are of importance in the core-collapse stage of supernovae and the rp-process. We report the study of GT transitions from the Tz=+3/2, 47Ti nucleus to the states in Tz=+1/2, 47V nucleus by the (3He,t) reaction. The experiment was carried out at the Research Center for Nuclear Physics (RCNP), Osaka [1] using a 3He beam of 140 MeV/nucleon [2-5]. An excellent energy resolution of 20 keV was achieved by applying the dispersion matching techniques. We could study GT transitions to individual states up to 12.5 MeV in 47V. In order to determine the strength of each transition, it was assumed that the GT transition strength B(GT) is proportional to the measured differential cross-section at 0° in the (3He,t) reaction [6]. Since a “standard B(GT) value” is available from the study of 47V b decay, B(GT) values were reliably derived. The observed GT strength spreads widely up to 12.5 MeV and are highly fragmented. These features were very different from the “compact” GT strength distribution observed in the 41K(3He,t)41Ca reaction having the same Tz=+3/2à+1/2 nature [7]. The GT strength distribution in 47V was well reproduced by the shell-model calculations. The GT transitions from the ground state of 47Ti to the three low-lying states in 47V and the M1 transitions from the isobaric analog state in 47V to the same low-lying states in 47V are analogous. It was found that the ratios of the strengths of these analogous GT and M1 transitions were similar. [1] http://www.rcnp.osaka-u.ac.jp. [2] Y. Fujita, et al., Phys. Rev. Lett. 95, 212501 (2005). [3] T. Adachi et al., Phys. Rev. C 73, 024311 (2006). [4] H. Fujita et al., Phys. Rev. C 75, 034310 (2007). [5] L. Popescu et al., Phys. Rev. C 79, 064312 (2009). [6] Y. Fujita, B. Rubio and W. Gelletly, Prog. Part. Nucl. Phys., 66, 549 (2011). [7] Y. Fujita et al., Phys. Rev. C 70, 054311 (2004).

DATA: 13-12-2012