Scattering Cross Sections of Argon and Atomic Oxygen to Thermal Electrons

摘要: The electron-scattering cross section for momentum transfer of several neutral species has been experimentally determined. An $S$-band microwave interferometer was employed to investigate the plasma produced by incident shock wave in a tube. This state equilibrium, so relative concentrations and electron velocity distribution were known. For electron-collision frequencies small compared with signal frequency, data could be intepreted yield scattering sections. argon atom measured from 1800 5500\ifmmode^\circ\else\textdegree\fi{}K. results agree previous drift measurements when those sections are averaged over Maxwellian velocities. Above 3000\ifmmode^\circ\else\textdegree\fi{}K oxygen molecule becomes dissociated oxygen-atom can measured. From 3000 4000\ifmmode^\circ\else\textdegree\fi{}K, this atomic is (1.2\ifmmode\pm\else\textpm\fi{}0.2) \ifmmode\times\else\texttimes\fi{} ${10}^{\ensuremath{-}15}$ ${\mathrm{cm}}^{2}$. molecular nitrogen small-collision-frequency requirement not fully satisfied. these gases approximately ${\mathrm{cm}}^{2}$ 2000 3500\ifmmode^\circ\else\textdegree\fi{}K, no observable dependency on gas density.