Energy straggling of 60 MeV 58Niq+ ions in thin carbon foils and gases

Abstract Energy straggling of 60 MeV 58 Ni q + ions in thin carbon foils and gas layers has been measured with a Q3D magnetic spectrograph in dependence of the incident and analysed charge state of the ions. The straggling increases with the number of electrons per gas molecule, thus showing strong correlation effects. In solid carbon, however, energy straggling is close to the data of deuterium gas. The small straggling in carbon is interpreted as an effect of the long range interaction of the heavy ions in dense solids. Furthermore, it is observed that energy straggling depends on the charge state of the projectiles unless the equilibrium charge state is reached.