Application of the thermal spike model for explanation of variations of surface structure of highly oriented pyrolytic graphite under bombardment by 86Kr and 209Bi fast ions with high ionization energy loss

Temperature effects in the highly oriented pyrolytic graphite (HOPG) under bombardment by ⁸⁶Kr (253 MeV) and ²⁰⁹Bi (710 MeV) heavy ions are studied in the framework of a three-dimensional thermal spike model. It is shown that the surface temperature of an HOPG target under bombardment by bismuth ions can exceed the sublimation temperature at particular values of the electron-phonon interaction coefficient. At the same time, the temperature at the target surface during bombardment of HOPG by krypton ions does not exceed the sublimation temperature over a wide range of variations in the electron-phonon interaction belongs. The calculations allow the explanation of the observed changes in the surface structure of HOPG single crystal under bombardment by ²⁰⁹Bi and ⁸⁶Kr ions.