ENERGY STRAGGLING OF 60 MEV NI-58(Q+) IONS IN THIN CARBON FOILS AND GASES

Energy straggling of 60 MeV Ni-58(q+) ions in thin carbon foils and ga s layers has been measured with a Q3D magnetic spectrograph in depende nce of the incident and analysed charge state of the ions. The straggl ing increases with the number of electrons per gas molecule, thus show ing strong correlation effects. In solid carbon, however, energy strag gling is close to the data of deuterium gas. The small straggling in c arbon is interpreted as an effect of the long range interaction of the heavy ions in dense solids. Furthermore, it is observed that energy s traggling depends on the charge state of the projectiles unless the eq uilibrium charge state is reached. (C) 1998 Elsevier Science B.V. All rights reserved.