In view of the striking implications of the recently measured g factors for the 21+ states of 42Ca and 44Ca we have supplemented this study with similar measurements on 46Ca. For all three isotopes we utilized the powerful technique of projectile Coulomb excitation in inverse kinematics combined with transient magnetic fields. In contrast to the positive g(21+) factor values for both 42,44Ca, implying large admixtures of particle-hole configurations from 40Ca core excitations, the g factor of 46Ca(2 1+), g=-0.19(12), is negative. This result is in very definite disagreement with the large positive value predicted by the large scale shell model (LSSM) calculations which included sd shell core excitations into the fp shell and accounted well for corresponding 42,44Ca results. The B(E2;01+→21+) deduced from the remeasured 46Ca(21+) lifetime is indeed substantially smaller than the corresponding value for 42Ca, again contrary to LSSM predictions. Both g(21 +) and B(E2) in 46Ca can be explained by full fp shell model calculations using the FPD6 interaction without invoking core excitations.
|Original language||English (US)|
|Number of pages||4|
|Journal||Physical Review C - Nuclear Physics|
|State||Published - Dec 2003|
All Science Journal Classification (ASJC) codes
- Nuclear and High Energy Physics