Nuclear charge distribution in the spontaneous fisson of 252Cf

Abstract

The fractional Cumulative Yields (FCY) of 108,109Ru, 137,138,139Xe, 139,140,141,142Ba and 146Ce in the spontaneous fission of 252Cf have been determined. These data alongwith literature data have been analysed to obtain charge distribution parameters viz: the most probablecharge (Z P) and the width parameter (σ Z) for the mass chains 105, 131, 138, 139, 140 and 141. Analysis of data indicates increase in charge polarization (ΔZ) with the asymmetry. In comparision to lighter fissioning systems such as 234U, 236U, 240Pu and 250Cf, observed increase in ΔZ as a function of asymmetry is found to be more and the general trend shows that ∂ΔZ/∂A increases with fissility parameter. This observation is explainable on the basis of increase in time of descent from saddle to scission with increasing fissility permittting more polarization.