Excitation of the O/sub 2/(a /sup 1/. delta. /sub g/) state by low energy electrons

Journal Article · Thu Oct 01 04:00:00 EDT 1981 · J. Chem. Phys.; (United States)

OSTI ID:6151033

Tachibana, K; Phelps, A V

Coefficients for the excitation of the a /sup 1/..delta../sub g/ metastable state of O/sub 2/ by low energy electrons in O/sub 2/--Ar mixtures have been measured using a drift tube technique. The time dependence of the absolute intensity of the 1.27 ..mu..m band emission was measured for 1% and 5% O/sub 2/ in Ar at total gas densities of (1--20) x 10/sup 24/ m/sup -3/. The electric field to gas density ratio E/N was varied from (0.3--10) x 10/sup -21/ V m/sup 2/, corresponding to calculated mean electron energies between about 0.8 and 4 eV. The measured decay constants yield a normalized diffusion coefficient for O/sub 2/(a /sup 1/..delta../sub g/) in Ar of (2.8 +- 0.2) x 10/sup 20/ m/sup -1/ s/sup -1/ and a rate coefficient for quenching by O/sub 2/ of (1.57 +- 0.1) x 10/sup -24/ m/sup 3/ s/sup -1/. Our experimental electron excitation coefficients agree satisfactorily with values calculated using previously derived sets of electron collision cross sections for O/sub 2/ and Ar.

• Research Organization: Joint Institute for Laboratory Astrophysics, National Bureau of Standards and University of Colorado, Boulder, Colorado 80309
• OSTI ID: 6151033
• Journal Information: J. Chem. Phys.; (United States), Journal Name: J. Chem. Phys.; (United States) Vol. 75:7; ISSN JCPSA
• Country of Publication: United States
• Language: English

Related Subjects

640304* -- Atomic
Molecular & Chemical Physics-- Collision Phenomena
74 ATOMIC AND MOLECULAR PHYSICS
COLLISIONS
CROSS SECTIONS
ELECTRON COLLISIONS
ELECTRON-MOLECULE COLLISIONS
ELECTRONIC STRUCTURE
ELEMENTS
EMISSION SPECTRA
ENERGY LEVELS
ENERGY-LEVEL TRANSITIONS
EXCITATION
EXCITED STATES
METASTABLE STATES
MOLECULE COLLISIONS
NONMETALS
OXYGEN
SPECTRA