Electron mobility in dense Argon gas at several temperatures

Abstract

The mobility of excess electrons in dense Argon gas has been measured as a function of the applied electric field E and of the gas density N at several temperatures in the range 142.6<T<200 K, encompassing the critical temperature T c =150.86 K. We report here measurements at densities up to N 7 nm maximum. This appears to be a crossover behavior between the positive density effect shown for T>T c and the small negative effect previously observed for T 90 K. In any case, the data at all temperatures confirm the interpretation of the anomalous density effect as being essentially due by the density-dependent quantum shift of the electron ground state kinetic energy in a disordered medium as a result of multiple scattering (MS) processes, although other MS processes do influence the outcome of the experiment.