Angle-resolved time-of-flight studies on ground-state neutrals formed by near-threshold excimer laser ablation of copper

The angle-resolved velocity distributions of neutral copper atoms created by near-threshold ultraviolet excimer laser ablation of polycrystalline copper foils are measured as a function of the polar desorption angle and the laser fluence. The obtained time-of-flight spectra can be fitted by elliptical Maxwell–Boltzmann distributions on a stream velocity. Integration of the spectra allows one to determine the kinetic energy of these atoms. This kinetic energy is hyperthermal (1 eV).