Studies of electron-molecule scattering at microelectronvolt energies using very-high-n Rydberg atoms.

Abstract

Atoms in very high Rydberg states, $100\ensuremath{\lesssim}n\ensuremath{\lesssim}1100$, are used to investigate electron-molecule interactions at electron energies extending down to a few microelectronvolts. At such energies the cross section for electron capture by CC${\mathrm{l}}_{4}$ is observed to vary inversely with electron velocity, indicative of an $s$-wave process. Studies with the polar target C${\mathrm{H}}_{3}$Cl suggest that dipole-supported states may be important in inelastic electron-polar molecule scattering at very low electron energies.