Electron capture strength for Ni60,62 and Ni58,60,62,64(p, n)Cu58,60,62,64 reactions at 134.3 MeV
Abstract
Background: The strength of electron capture for medium mass nuclei has a significant effect on the evolution of supernovae. There is insufficient knowledge of these strengths and very little data for important radioactive nuclei. Purpose: Determine whether it is feasible to obtain EC strength from studies of To+1 excitations in (p, n) reactions, and whether this might yield information for radioactive nuclei. Methods: Cross sections for the Ni58,60,62,64(p, n)Cu58,60,62,64 reactions were measured over the angular range of 0.3∘ to 11.6∘ at 134.3 MeV using the IUCF neutron time-of-flight facility. Results: The To+1 excitations in Ni60,62 were identified by comparison with inelastic proton scattering spectra, their B(GT) were extracted, and the corresponding electron capture rates in supernovae were calculated. Data from the TRIUMF (n, p) experiments at 198 MeV were reanalyzed; the electron capture rates for the reanalyzed data are in moderately good agreement with the higher resolution (p, n) results, but differ in detail. The possibility of future measurements with radioactive nuclei was considered. Conclusions: It may be possible to obtain low-lying electron capture strength for radioactive nuclei by studying (p, n) reactions in inverse kinematics.
- Publication:
-
Physical Review C
- Pub Date:
- December 2008
- DOI:
- 10.1103/PhysRevC.78.065803
- arXiv:
- arXiv:0805.2374
- Bibcode:
- 2008PhRvC..78f5803A
- Keywords:
-
- 25.40.Kv;
- 23.40.-s;
- 24.30.Gd;
- 95.30.Cq;
- Charge-exchange reactions;
- Beta decay;
- double beta decay;
- electron and muon capture;
- Other resonances;
- Elementary particle processes;
- Nuclear Experiment
- E-Print:
- Submitted to Physical Review C