Vibrationally stimulated ionization of carbon monoxide in optical pumping experiments

Effect of electron density on shock wave propagation in optically pumped plasmas

“…29,30 The gas pressure and temperature in these plasmas ͑Pϳ100 Torr, T ϳ400-700 K͒, 30 as well as the electron density and electron temperature ͑n e ϳ10 10 -10 11 cm Ϫ3 , T e ϳ0.5 eV͒ 30,31 are similar to those achieved in glow discharges. In addition, our previous experiments 32,33 suggest that the electron density and the gas temperature in such plasmas can be varied independently.…”

“…The VV processes then continue to populate higher vibrational levels, up to vϭ40, 29,30 which are not directly coupled to the laser radiation. The large heat capacity of the Ar diluent, as well as conductive and convective cooling of the gas flow, enables sustaining fairly low translational/rotational mode temperatures in the cell (Tϭ600-700 K).…”

“…However, at steady-state conditions, the average vibrational mode energy of the CO corresponds to a few thousand degrees Kelvin. 29,30 Thus a strong disequipartition of energy can be maintained in the cell, characterized by very high vibrational mode energy and a low translational/rotational mode temperature. As shown in Fig.…”

“…Ionization of highly excited CO molecules in the cell occurs by the associative ionization mechanism, in collisions of two highly vibrationally excited molecules when the sum of their vibrational energies exceeds the ionization potential, 29,[31][32][33] CO͑v ͒ϩCO͑ w ͒→͑ CO͒ 2 ϩ ϩe Ϫ ,…”

Time-resolved Fourier-transform infrared spectroscopy of optically pumped carbon monoxide

“…In particular, the vibration-to-electronic (V-E) processes, in which energy is transferred from highly vibrationally excited levels of the ground electronic state to a low-lying excited electronic state, with subsequent ultraviolet and visible band radiation, have and NO [9,10]. Ionization in collisions of two vibrationally excited CO molecules pooling their energies together has been studied in [ 11,121. Predictive analysis of kinetics of these energy transfer processes, coupled to the high vibrational level populations, require precise knowledge of the V-V rates.…”