Actinide yields from the reactions of 40Ca and 48Ca with 248Cm

Abstract

Radiochemical techniques were applied to determine the actinide yields for nuclides with mass numbers below and above that of the target from the reaction 48Ca + 248Cm at energies near the interaction barrier. This work was initiated in the hope that the very neutron-rich projectile 48Ca might give access to new neutron-rich isotopes of target-like actinide elements by nucleon transfer reactions. However, for trans-target elements, the use of 48Ca did not result in increased production rates for such isotopes compared with those obtained in previous investigations. In contrast, rather neutronrich isotopes of below-target elements were observed at a remarkably high cross-section level. This observation is interpreted as a massive mass drift towards symmetry for this system. These investigations have been extended to the system 40Ca + 248Cm to explore the effect of the very different neutron-to-proton N Z ratios of 40Ca and 48Ca on the production of heavy target-like products.