The temperature of the track

The energy deposition of swift charged particles penetrating solids is accompanied by such processes as particle (electron, atom, ion, molecular ion, photon …) emission and/or a change of the solid along the particle track. The energy, velocity and mass distribution of such secondary particles obtained from thin solids (such as carbon, polyhydrocarbon, isolators and conductors) penetrated by projectiles (e.g. Ar 1.8 MeV) was measured quantitatively. A number of direct and indirect production mechanisms contribute to the internal source of electrons and secondary ions. The analysis of the ejected radicals give information on the emission processes, the temperature, the charge and the time scale of energy deposition near the surface of the solid which, eventually, become responsible for the track formation.