Skip to main content
OSTI.GOVU.S. Department of Energy Office of Scientific and Technical Information
U.S. Department of Energy
Office of Scientific and Technical Information
 

Absolute experimental differential and integral electron excitation cross sections for atomic oxygen 1. The (/sup 3/P. -->. /sup 3/S/sup 0/) transition (1304 A) at 100 eV

Journal Article · · J. Geophys. Res.; (United States)
;

The absolute differential electron scattering cross section for the atomic oxygen (/sup 3/P..-->../sup 3/S/sup 0/) transition (1304 A) has been measured at 100-eV electron impact energy. The experimental apparatus was a variable angle and incident energy electron spectrometer coupled to a microwave discharge free supersonic jet expansion source. The source produced an intense jet containing O/sub 2/, H, O, and He with an O/O/sub 2/ ratio typically greater than 2.5. Relative densities of species in the jet were determined from the zero angle forward electron energy loss spectrum and the known optical oscillator strengths for transitions in each species. Measured relative differential cross sections (DCS) were put on an absolute scale by comparison with the known DCS for the He 2 /sup 1/P transition. As a check on the atomic oxygen values a simultaneous determination was made of the DCS for the H (1s)..-->..H (n = 2) transition. Results for this transition were in excellent agreement with previous experimental and theoretical results. An additional check on the DCS values for O and H was given by the extrapolation within experimental error of the generalized oscillator strengths calculated from the measured DCS values to the optical oscillator strengths at zero momentum change. The O /sup 3/S/sup 0/ DCS is extremely forward peaked and decreases by almost 5 orders of magnitude from 0/sup 0/ to 90/sup 0/ scattering angle. The integral, direct excitation, cascade-free cross section at 100 eV is 6.4 (+- 1.0) x 10/sup -18/ cm/sup 2/.

Research Organization:
Department of Chemistry, The Johns Hopkins University, Baltimore, Maryland
OSTI ID:
6018925
Journal Information:
J. Geophys. Res.; (United States), Journal Name: J. Geophys. Res.; (United States) Vol. 91:A3; ISSN JGREA
Country of Publication:
United States
Language:
English

Similar Records

Absolute differential and integral electron excitation cross sections for atomic oxygen. 5. Revised values for the /sup 3/P. -->. /sup 3/S/sup 0/ (1304 A) and /sup 3/P. -->. /sup 3/D/sup 0/ (989 A) transitions below 30 eV
Journal Article · Wed Jun 01 00:00:00 EDT 1988 · J. Geophys. Res.; (United States) · OSTI ID:6952545
Absolute experimental differential and integral electron excitation cross sections for atomic oxygen 4. The (/sup 3/P-. -->. 3s'' /sup 3/P/sup 0/), (/sup 3/P. -->. 2s 2p/sup 5/ /sup 3/P/sup 0/), (/sup 3/P. -->. 4d' /sup 3/P/sup 0/) autoionizing transitions (878, 972, and 770
Journal Article · Thu Dec 31 23:00:00 EST 1987 · J. Geophys. Res.; (United States) · OSTI ID:5423617
Electron-impact excitation of the 6p7s {sup 3}P{sub 1} state of Pb atom at small scattering angles
Journal Article · Tue May 15 00:00:00 EDT 2007 · Physical Review. A · OSTI ID:20982531

Related Subjects

640304* -- Atomic
Molecular & Chemical Physics-- Collision Phenomena
74 ATOMIC AND MOLECULAR PHYSICS
ATMOSPHERIC CHEMISTRY
ATOM COLLISIONS
CHEMISTRY
COLLISIONS
CROSS SECTIONS
DATA
DIFFERENTIAL CROSS SECTIONS
ELECTRON COLLISIONS
ELECTRON-ATOM COLLISIONS
ELEMENTS
ENERGY RANGE
ENERGY SPECTRA
ENERGY-LEVEL TRANSITIONS
EV RANGE
EV RANGE 10-100
EXCITATION
EXPERIMENTAL DATA
INFORMATION
INTEGRAL CROSS SECTIONS
NONMETALS
NUMERICAL DATA
OXYGEN
SPECTRA