Accession Number : AD0736433

Title :   Formation of H(2p) and H(2s) in Collisions of Protons and Hydrogen Atoms with Hydrogen Molecules.

Descriptive Note : Research rept. 1 Jul 70-30 Jun 71,

Corporate Author : AEROSPACE CORP EL SEGUNDO CALIF LAB OPERATIONS

Personal Author(s) : Birely,John H. ; McNeal,Robert J.

Report Date : 15 DEC 1971

Pagination or Media Count : 46

Abstract : Cross sections for emission of Lyman-alpha radiation owing to formation of H(2p) and H(2s) in collisions of 5-15 keV protons and hydrogen atoms with molecular hydrogen have been determined. The intensity of Lyman -alpha emitted spontaneously from H(2p) was measured at 54.7 or 125.3 deg with respect to the projectile beam in an essentially field-free collision chamber with an oxygen-filtered photometer calibrated by reference to previous results for H(+) on Ar. The increase in intensity of Lyman-alpha when an electric field, oriented in the direction of the beam, was applied within the collision chamber has been used to derive separate cross sections for formation of H(2s) owing to projectile and dissociative excitation. The experimental configuration was designed to minimize the effect of polarization of the light emitted from H(2p) and H(2s). The total cross section for formulation of H(n=2) via projectile excitation exceeds that for dissociative excitation in either H(+) or H impact. (Author)

Descriptors :   (*HYDROGEN, EXCITATION), (*PROTON BOMBARDMENT, HYDROGEN), FLUORESCENCE, ULTRAVIOLET RADIATION, ELECTRON TRANSITIONS, DIFFERENTIAL CROSS SECTIONS, DISSOCIATION, AURORAE, MAGNETOSPHERE, SOLAR WIND

Subject Categories : Atmospheric Physics
      Physical Chemistry

Distribution Statement : APPROVED FOR PUBLIC RELEASE