Electron captures on iron-group nuclei near 56Ni play an important role in the evolution of type Ia and type II supernovae. A new technique that allows the study of Gamow-Teller (GT) strengths from unstable nuclei has been developed at NSCL and used to probe the GT response of 56Ni. The 56Ni(p,n)56Cu charge-exchange reaction at 110MeV/u was employed to extract GT strengths from 56Ni for the first time. Because of isospin symmetry, the extracted strength distribution is also valid for the 56Ni → 56Co electron-capture direction, which is most important for astrophysical applications. The results were compared with shell-model theory employing two modern interactions, GXPF1A/J and KB3G. The calculation with the GXPF1A/J interaction provides a better match to the experimental results. Besides the results for 56Ni, newly extracted Gamow-Teller strengths from the 55Co(p,n) reaction are presented.
|Journal||Proceedings of Science|
|State||Published - 2012|
|Event||12th International Symposium on Nuclei in the Cosmos, NIC 2012 - Cairns, QLD, Australia|
Duration: Aug 5 2012 → Aug 12 2012