Accession Number : AD0625480

Title :   ELECTRONIC AND IONIC REACTIONS IN ATMOSPHERIC GASES.

Descriptive Note : Yearly technical summary rept., 1 Sep 64-31 Aug 65,

Corporate Author : GENERAL DYNAMICS CORP SAN DIEGO CALIF GENERAL ATOMIC DIV

Personal Author(s) : Stebbings,R. F. ; Fineman,M. A. ; McGowan,J. W. ; Turner,B. R.

Report Date : 01 DEC 1965

Pagination or Media Count : 133

Abstract : Collisions involving charge transfer and charged rearrangement between some of the positive ions and neutral molecules present in the earth's upper atmosphere have been investigated in a crossed beam experiment at energies within the range 2 to 200 eV. The charged reaction products are identified in a mass spectrometer, and absolute cross sections for their production are obtained. Interpolation between these values and those obtained at thermal energy in afterglow experiments provides information on the variation of the cross sections with energy in the intervening energy interval. The influence of excited ions is examined in some detail. Ionization of N2 and H2 just above threshold has been investigated using monoenergetic electrons obtained with a 127-deg electrostatic energy selector. In both cases there was evidence of ionization occurring by autoionization as well as direct ionization. The agreement between our electron impact results and those obtained by photoionization for the autoionization processes is compared. In the case of H2, we have interpreted the structure in the second-derivative electron impact spectrum to be due to the rotational states of H2 and H2(+) taking part in the ionization process. (Author)

Descriptors :   (*GAS IONIZATION, UPPER ATMOSPHERE), (*UPPER ATMOSPHERE, GAS IONIZATION), IONS, MOLECULES, ELECTRONS, NITROGEN, HYDROGEN, ELECTROSTATICS, PHOTOCHEMICAL REACTIONS, REACTION KINETICS, PLASMAS(PHYSICS)

Subject Categories : Atmospheric Physics
      Plasma Physics and Magnetohydrodynamics

Distribution Statement : APPROVED FOR PUBLIC RELEASE