Hydrogen vibrational population distributions and negative ion concentrations in a medium density hydrogen discharge

The vibrational population distribution for hydrogen molecules in a hydrogen discharge has been calculated taking into account electron collisional excitation, molecule‐molecule, and wall collisional de‐excitation processes. Electronic excitation processes include vibrational excitation by 1 eV thermal electrons acting through the intermediary of the negative ion resonances, and vibrational excitation caused by the radiative decay of higher singlet electronic states excited by a small population of 60 eV electrons in the discharge. The molecules are de‐excited by molecular collisions transferring vibrational energy into translational energy, and by wall collisions. The distributions exhibit a plateau, or hump, in the central portion of the spectrum. The relative concentration of negative ions is calculated assuming dissociative attachment of the low temperature electrons to vibrationally excited, non‐rotating molecules. The ratio of negative ions to electrons in the discharge is calculated to be of order ...

[1]  K. Leung.  H- ION FORMATION FROM A SURFACE CONVERSION TYPE ION SOURCE , 1981 .

[2]  M. Bacal,et al.  Measurement of vibrational populations in low‐pressure hydrogen plasma by coherent anti‐Stokes Raman scattering , 1981 .

[3]  A. Karo.  Molecular potentials and relaxation dynamics , 1981 .

[4]  J. Hiskes.  Formation of negative hydrogen ions in surface and volume processes , 1981 .

[5]  William G. Graham,et al.  Pressure and electron temperature dependence of H− density in a hydrogen plasma , 1981 .

[6]  J. Hiskes.  Cross sections for the vibrational excitation of the H2(X1∑+g) state via electron collisional excitation of the higher singlet states , 1980 .

[7]  J. M. Wadehra.  Rates of dissociative attachment of electrons to excited H2 and D2 , 1979 .

[8]  J. M. Wadehra.  Low-energy collisions of D/sup +/ with D and He/sup 2 +/ with He , 1979 .

[9]  G. W. Hamilton,et al.  H - and D - Production in Plasmas , 1979 .

[10]  G. W. Hamilton,et al.  Measurement of H- density in plasma by photodetachment. , 1979, The Review of scientific instruments.

[11]  J. M. Wadehra,et al.  Vibrational- and rotational-state dependence of dissociative attachment in e-H/sub 2/ collisions , 1978 .

[12]  S. Wong,et al.  Effect of vibrational and rotational excitation on dissociative attachment in hydrogen , 1978 .

[13]  M. Bacal,et al.  Equilibrium density of h- in a low pressure hydrogen plasma , 1977 .

[14]  M. Capitelli,et al.  A theoretical calculation of dissociation rates of molecular hydrogen in electrical discharges , 1977 .

[15]  G. D. Billing,et al.  VV and VT rate coefficients in H2 by a quantum-classical model , 1976 .

[16]  J. Ducuing,et al.  Vibrational relaxation of H2 in the range 500–40°K , 1974 .

[17]  G. Schulz.  Resonances in electron impact on atoms , 1973 .

[18]  I. Smith,et al.  Vibrational relaxation in atom-exchange reactions: A classical, Monte Carlo, trajectory study , 1973 .

[19]  G. Adam,et al.  Shape restricted wavefunctions: Two center spherical limits for H+2 , 1970 .

[20]  J. R. Peterson,et al.  H + + H − Mutual Neutralization Cross Section Obtained with Superimposed Beams , 1970 .

[21]  M. Harrison,et al.  A measurement of the cross section for charge exchange in H+-H- collisions , 1969 .

[22]  R. G. Rehm,et al.  Vibrational Relaxation of Anharmonic Oscillators with Exchange‐Dominated Collisions , 1968 .

[23]  J. W. Fox,et al.  ELASTIC CROSS SECTIONS OF HYDROGEN ATOMS. , 1967 .

[24]  James C. Keck,et al.  DIFFUSION THEORY OF NONEQUILIBRIUM DISSOCIATION AND RECOMBINATION , 1965 .