MASS YIELD AND ANGULAR-DISTRIBUTION OF RARE-EARTH ELEMENTS PRODUCED IN PROTON-INDUCED FISSION OF PU-244

In the fission system Pu-244+p, formation cross sections of rare earth products were observed in the proton energy range 10 to 16 MeV, and t heir angular distributions were measured in detail of proton energy of 15 MeV. The highest mass number of rare earth products was 162 which corresponded to a highly asymmetric mass division of A(H)/A(L) approxi mate to 2. The incident energy dependence and angular anisotropies of rare earth products were found to be the same, even for highly asymmet ric mass division, and no clear evidence was observed for the effect o f neutron numbers 50 and 97 on cross section and angular anisotropy. T hese observations lead to the conclusion that the fission process, lea ding to highly asymmetric mass division, experiences the same saddle p oint in the course of deformation toward scission as that for other ty pical asymmetric mass division.