An attempt to understand secondary photon emission

If excited neutrals which are sputtered from bombarded solids have a thermal origin, the yields of photons emitted by these excited neutrals will be governed by a Boltzmann factor. This idea was tested experimentally with Be, BeO, Al, Al2O3, Sc, GaAs, Y, In, and Tl. A Boltzmann factor was in fact obeyed but the inferred temperatures were insensitive to the variation of target mass, ion mass, ion energy, and target crytallinity. It is concluded that a thermal-excitation model accounts for many of the details of excited-state production but that the inferred temperatures have an origin other than in conventional thermal spikes. (Auth.)