Charge distribution in the symmetric region of high energy proton induced fission of uranium

As a continuation of the studies in high-energy proton-induced fission at CERN, some yields of indium and tin isotopes from the fission of uranium with 570 MeV and 18.2 GeV protons are reported. The yields have been determined by conventional radiochemical methods including the use of an electromagnetic isotope separator. These yields are used together with published yields of isotopes of other elements in the same mass region to construct charge dispersion curves for A = 117. The charge dispersion curve at 18.2 GeV is double-humped, and one of the two parts is identical in form and position to the 570 MeV. Also Zp, the most probable charge for each mass number, as well as the width of the charge dispersion curve as a function of fission product mass and of proton energy has been established. Although Zp moves slightly with energy below 570 MeV, it seems that in the symmetric fission region the width of the charge dispersion curve is independent of mass number and proton energy. (author)