The optical excitation function for the <i>G</i><sup>1</sup>Σ<sup>+</sup><sub>g</sub> →<i>B</i><sup>1</sup>Σ<sup>+</sup><sub>u</sub> transition of the H<sub>2</sub> spectrum has been determined for the electron impact energies in the range 0-500 eV and at H<sub>2</sub> gas pressures ≤ 30 mtorr. Measurements of the absolute emission cross section for the λ = 4634 Å [<i>G</i> → <i>B</i>(0,0)<i>P</i>1,<i>R</i>2,<i>R</i>3] vibration-rotational line blend have been carried out at 200 eV incident electron energy. Measurements of the <i>G</i><sup>1</sup>Σ<sup>+</sup><sub>g</sub>(ν′ = 0) state radiative lifetime have also been carried out and yield a single-mode decay, with a lifetime of ∼30 ns. Both dc intensity and time-solved lifetime measurements are observed to be independent of H<sub>2</sub> gas pressure and electron beam current over the regions ∼ 2 to 50 mtorr and 5 µA to 1 mA, respectively.
© 1978 Optical Society of America
Richard J. Anderson, J. Watson, Jr., and Francis A. Sharpton, "Electron impact excitation of the G 1Σ+g state of H2," J. Opt. Soc. Am. 67, 1641-1643 (1977)