Line strengths and updated molecular constants for the C2 Swan system

Abstract

New rotational line strengths for the C2 Swan system have been calculated for vibrational bands with v'=0-10 and v"=0-9, and J values up to J=34-96, based on previous observations in 30 vibrational bands. Line positions from several sources were combined with the results from recent deperturbation studies of the v'=4 and v'=6 states, and a weighted global least squares fit was performed. We report the updated molecular constants. The line strengths are based on a recent ab initio calculation of the transition dipole moment function. A line list has been made available, including observed and calculated line positions, Einstein A coefficients and oscillator strengths (f-values). The line list will be useful for astronomers and combustion scientists who utilize C2 Swan spectra. Einstein A coefficients and f-values were also calculated for the vibrational bands of the Swan system.

23 pages, 5 figures, submitted to JQSRT, new C2 Swan line list available at http://bernath.uwaterloo.ca/download/AutoIndex.php?dir=/C2/ (C2SwanLineList2012.txt); Changes for version 2 - typo in equations 4 and 5, line list updated due to typo in code causing f-values in line list to be calculated incorrectly (all other values in list, and all values in tables are correct)

References in corpus (2)

• The Galactic R Coronae Borealis stars : the C2 Swan bands, the carbon problem, and the 12C/13C ratio
• Abundances and rotational temperatures of the C2 interstellar molecule towards six reddened early-type stars

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