Measurement of Total Cross Sections for the Scattering of Low-Energy Electrons by Lithium, Sodium, and Potassium

Absolute total cross sections for the scattering of 2–18-eV electrons by cesium atoms

“…If the electron beam is allowed to enter the interaction region (by switching the voltage at the center element of the decelerating lens from the negative cutoff voltage to the appropriate positive focusing voltage), some of the atoms in the beam will collide with electrons and will be recoiled away from the beam axis. The atomic beam current will be reduced by an amount [1] and (1/V) is the mean inverse atomic speed over the atomic beam speed distribution (which in this experiment is non-Maxwellian, determined mainly by the hexapole magnet}. This assumes that the geometry of the beams overlap volume is such that all the collected electrons cross the atomic beam.…”

Negative-ion resonances in total cross sections for slow electron-sodium collisions

“…Negative-ion formation in electronsodium (e-Na) scattering has attracted substantial theoretical and experimental efforts owing to its extreme sensitivity to the electron correlation effects. Experimental studies for sodium negative-ion resonances have been carried out in electron scattering [6][7][8][9][10][11][12], laser photodetachment technology [13], and electron transmission spectroscopy [14,15]. On the theoretical side, the low-lying negative-ion states were predicted by several different theoretical models, such as the close-coupling approach [16][17][18], the multiconfigurational Hartree-Fock method [19], and variational [20], effectiverange [21], and relativistic R-matrix techniques [22].…”

Energy Transfer Processes in the Production of Excited States in Reacting Rocket Flows

“…(vibrationally-induced chemistry was first observed in optically pumped CO in [36]). Finally, both theoretical calculations of the V-T rates for CO-CO [20] and measurements of the V-T rates CO-Ar at high vibrational levels [37] show them to be far too slow to affect the vibrational level populations at v~40, especially at the low temperatures of T=100-300 K. Note that dramatic increase of the state-specific vibrational relaxation rates above a threshold vibrational quantum level, induced by chemical reactions or intermolecular electronic coupling, has been also previously observed in NO (v>14) [38], O2 (v>26) [39], and N0 2 (vibrational energy greater than 10,000-12,000 cm" 1 ) [40].…”

“…The method used in the present work is somewhat similar to the approach developed by Skrebkov and Smirnov [36], which is perhaps the most advanced of available analytic models.…”

“…The experimental electron transport cross-sections for N 2 , 0 2 , NO, Na, K, and Cs necessary for the plasma electric conductivity calculations, are taken from [26][27][28]36].…”