Charge distribution of light mass fission products in the fast neutron induced fission of 237Np, 241Am and 243Am

In the fast neutron induced fission of 237Np, 241Am and 243Am, fractional cumulative yields (FCY) of various light mass fission products have been measured for the first time by using an off-line γ-ray spectrometric technique. The most probable charge (ZP) and the experimental charge polarization (ΔΖEXPT) as a function of fragment mass were obtained. The ΔΖEXPT values for the light mass chains from the present work and for the heavy mass chains from earlier work show a decreasing trend towards symmetric split with fluctuations for some of the mass chains due to the effect of shell closure proximity. The ΔΖMPE values based on minimum potential energy surface were theoretically calculated, which also shows a systematic decrease trend with the approach of symmetric split without any fluctuation due to the liquid drop behaviour of the fissioning nucleus. •FCY of light mass fission products in the (n,f) reactions of 237Np, 241Am and 243Am were measured.•From the FCY values, ZP and ΔΖEXPT values as a function of fragment mass were deduced.•The ΔZEXPT values do not show an oscillating nature due to the absence of odd-even staggering.•With the approach of symmetric split, the ΔZEXPT values show a systematic decreasing trend.•The ΔZEXPT values show a local fluctuation around the region of spherical proton and neutron shells