Fission product yields in 238Np thermal fission

Relative cumulative yields for 23 products in the range A=131-155 thermal fission of short-lived odd-odd 238Np nuclide are determined, using mass spectrometric method. The curve of mass yield in the region of heavy product peak is plotted, the absolute yields of the above-mentioned masses and the main parameters of the heavy product peak are evaluated. Irregularities in the curve of fission product mass distribution, observed in the ranges of mass yields A=134-136, A=137-140, A=144 and A=151-152, are explained in the framework of the Wilkins-Steinberg-Chasman statistical model of fission