The reduced transition probabilities B(E2;0g.s.+→21+) of the Ar46 and Ca44 nuclei were studied using the Coulomb excitation technique at intermediate energy at the LISE/GANIL facility. The in-flight γ rays, emitted after the Coulomb excitation of their first 2+ states, were detected in an array of 64BaF2 crystals. The present B(E2↑) value for Ca44, 475(36) e2fm4, agrees well with the value of 495(35) e2fm4 obtained by averaging results of previous experiments. Consistent B(E2;0g.s.+→21+) values of 225(29) e2fm4 and 234(19) e2fm4 have been obtained for Ar46 from an absolute and a relative measurement, normalized to the Ca44 value. Both results agree with the ones obtained with the same experimental technique at the NSCL facility but are a factor of 2 smaller than the shell model predictions. The drop in B(E2;0g.s.+→21+) in the Ar chain at N=28, confirmed in this experiment, shows that Ar46 is sensitive to the N=28 shell closure.
ASJC Scopus subject areas
- Nuclear and High Energy Physics