Spontaneous Raman scattering has been used to measure the effective vibrational temperature of the v=1 level as a function of input power in a self-sustaining low pressure dc glow discharge in pure H2 and D2 gases. A nonmonotonic dependence of vibrational temperature on input specific power, yielding Tv=1440–1960 °K in H2, has been measured downstream of the discharge. Results of numerical calculations modeling the discharge/afterglow are presented. The agreement between theory and experiment is good and suggest that the behavior observed is caused by the effect of the temperature dependent vibrational–translation energy transfer rate.

Self-consistent dissociative attachment and vibrational excitation cross sections for F2 have been calculated using Herzenberg’s theory of resonant electron scattering. It has been found that the observed electron–F2 attachment data can be explained by a low energy shape resonance. Potential parameters for the 2Σ+u negative ion were varied in order to fit predicted attachment cross sections to measured rate constant data. The best fit was obtained for a negative ion curve which crosses the F2 ground state in the vicinity of the equilibrium internuclear separation, in good agreement with an ab initio calculation for this state. The associated total vibrational cross section has a peak of about 2.0×10−16 cm2 at an incident electron energy of 0.45 eV. A strong dependence of attachment rate on F2 vibrational state is predicted.

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An experimental arrangement for the measurement of singly stimulated two-photon emission and anti-Stokes Raman scattering from metastable deuterium atoms is described. The atoms, produced by charge exchange between cesium vapor and 5-keV deuterons, are subjected to intense light pulses from a Nd-glass laser. The generated photons are detected at the exit slit of a vacuum-uv spectrometer. The results are compared with theoretical calculations by Z ernik.

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