NASA Logo, External Link
Facebook icon, External Link to NASA STI page on Facebook Twitter icon, External Link to NASA STI on Twitter YouTube icon, External Link to NASA STI Channel on YouTube RSS icon, External Link to New NASA STI RSS Feed AddThis share icon
 

Record Details

Record 66 of 15418
Differential electron scattering cross sections for the first optically forbidden and resonance transitions in Mg II, Zn II and Cd II
Author and Affiliation:
Williams, I. D.(Jet Propulsion Lab., California Inst. of Tech., Pasadena, CA, United States)
Chutjian, A.(Jet Propulsion Lab., California Inst. of Tech., Pasadena, CA, United States)
Mawhorter, R. J.(California Institute of Technology, Jet Propulsion Laboratory, Pasadena, United States)
Abstract: Differential electron scattering cross sections have been measured for dipole-forbidden and resonance transitions in Mg II, Zn II and Cd II in the angular range theta = 4-17 deg at 50 eV. These provide the first recorded angular distributions for an optically forbidden transition. It is found that while the cross section for excitation of the 4s (2)S-3d(9)4s(2) (2)D transition in Zn II is small, those for the 3s (2)S-3d (2)D, 4s (2)S (unresolved lines) in Mg II, and the 5s (2)S-4d(9)5s(2) D in Cd II are comparable in magnitude with the cross sections for resonance excitation. In addition, for Cd II it is found that the allowed and forbidden transitions have very similar angular distributions, and it is proposed that excitation to the 2D state may be dominated by a virtual 'double-dipole' transition via the 2P state. Also, the total excitation cross section of the resonance 2P state in Cd II is a factor of four higher than that predicted by the Gaunt factor approximation, suggesting that the accepted value for the oscillator strength may be too low.
Publication Date: Jul 28, 1986
Document ID:
19870025699
(Acquired Nov 28, 1995)
Accession Number: 87A12973
Subject Category: ATOMIC AND MOLECULAR PHYSICS
Document Type: Journal Article
Publication Information: Journal of Physics B - Atomic and Molecular Physics (ISSN 0022-3700); 19; 2189-219
Publisher Information: United Kingdom
Financial Sponsor: NASA; United States
Organization Source: Jet Propulsion Lab., California Inst. of Tech.; Pasadena, CA, United States
Description: 10p; In English
Distribution Limits: Unclassified; Publicly available; Unlimited
Rights: Copyright
NASA Terms: ELECTRON SCATTERING; FORBIDDEN TRANSITIONS; METALLIC PLASMAS; OPTICAL TRANSITION; SCATTERING CROSS SECTIONS; CADMIUM; MAGNESIUM; OSCILLATOR STRENGTHS; RESONANCE LINES; ZINC
Imprint And Other Notes: Journal of Physics B - Atomic and Molecular Physics (ISSN 0022-3700), vol. 19, July 28, 1986, p. 2189-2198. Research supported by the National Research Council, National Academy of Sciences, and NASA.
Miscellaneous Notes: Research supported by the National Research Council, National Academy of Sciences, and NASA
Availability Source: Other Sources
› Back to Top
Find Similar Records
NASA Logo, External Link
NASA Official: Gerald Steeman
Site Curator: STI Program
Last Modified: August 18, 2011
Contact Us