DIFFERENTIAL ION ENERGY-LOSS IN MULTIPLY IONIZING COLLISIONS

M. Schulz1,5, R. Moshammer1, W. Schmitt1, H. Kollmus1, R. Mann2, S.
Hagmann3, H. Rothard4, R.E. Olson5, J. Ullrich1

1Fakult=E4t f=FCr Physik, Universit=E4t Freiburg, 79104 Freiburg, Germany
2Gesellschaft f=FCr Schwerionenforschung (GSI), 64291 Darmstadt, Germany
3JRM, Kansas State University, Manhattan, USA
4CIRIL, 14040 Caen, France
5University of Missouri, Rolla, USA

A kinematically complete experiment for single, double, and triple
ionization in 3.6 MeV/amu Au53+ --> Ne collisions was performed.  A new
method to determine ion energy-loss spectra with unprecedented resolution
is introduced.  With this method it is possible for the first time to
determine the energy loss separately for different collision processes.
Our studies represent a crucial step in modelling stopping powers of dense
matter on a microscopic level.