ON IONIC CHARGE-DISTRIBUTIONS OF HEAVY EVAPORATION RESIDUES PASSING THROUGH A CARBON FOIL

Parameters of the ionic charge distributions, i.e., mean charge values and charge distribution widths for very heavy (Z greater-than-or-equa l-to 53) ions passing through a carbon foil were analyzed from the vie w point of applicability of known empirical systematics. Strong deviat ions (up to 60%) for experimental mean charge values were obtained fro m those deduced from empirical formulae at ion energies of less-than-o r-equal-to 0. 1 MeV/amu. Corrections providing a general agreement wit h the experimental data within +/-6% at the ion energies of 0.001 less -than-or-equal-to E less-than-or-equal-to 10 MeV/amu to the formula of Shima et al. are proposed. New systematics of the widths of charge di stributions are also presented. The obtained systematics were used in ion-optical calculations of transportation of evaporation residues thr ough the electrostatic recoil separator VASSILISSA.