Translational spectroscopy of metastable fragments produced by dissociative excitation of atmospheric gases by electron impact. I. Nitrogen

Journal Article · Sun Aug 01 04:00:00 EDT 1976 · Phys. Rev., A; (United States)

DOI:https://doi.org/10.1103/PhysRevA.14.695· OSTI ID:7359937

Wells, W C; Borst, W L; Zipf, E C

Kinetic-energy spectra of long-lived high-Rydberg nitrogen atoms produced by electron impact dissociative excitation were measured using a time-of-flight apparatus. Four principal features were found in the fragment kinetic-energy spectra with peaks at 0.6, 2.4, 3.4, and 6.7 eV. The excitation function exhibited a sharp resonance-like behavior near a threshold of 24.1 eV, corresponding to fragment production of N(/sup 4/S) + N**, where N** is a high-Rydberg atom with an energy near the ionization limit of N(14.54 eV). The observed features are discussed in terms of the core-ion model of high-Rydberg dissociation. The data are compared with other dissociative excitation and dissociative ionization work. The maximum differential cross section for the production of energetic long-lived high-Rydberg N atoms was found to be dsigma/d..cap omega.. approx. = 9 x 10/sup -20/ cm/sup 2/ sr/sup -1/ within a factor of 2 at an electron energy of 180 eV and at an angle of 90degree with respect to the electron beam. Geophysical implications of these measurements concerning heating of the atmosphere, radiative transfer of resonance radiation, and chemical reactions are mentioned briefly. (AIP)

• Research Organization: Lockheed Palo Alto Research Laboratory, Lockheed Missiles and Space Company, Palo Alto, California 94304
• OSTI ID: 7359937
• Journal Information: Phys. Rev., A; (United States), Journal Name: Phys. Rev., A; (United States) Vol. 14:2; ISSN PLRAA
• Country of Publication: United States
• Language: English

Related Subjects

640304* -- Atomic
Molecular & Chemical Physics-- Collision Phenomena
74 ATOMIC AND MOLECULAR PHYSICS
ATOM COLLISIONS
COLLISIONS
CROSS SECTIONS
CRYOGENIC FLUIDS
DISSOCIATION
ELECTRON COLLISIONS
ELECTRON-ATOM COLLISIONS
ELEMENTS
ENERGY
ENERGY SPECTRA
ENERGY-LEVEL TRANSITIONS
EXCITATION
FLUIDS
KINETIC ENERGY
NITROGEN
NONMETALS
SPECTRA