IDENTIFICATION AND INTENSITIES OF THE ``FORBIDDEN'' $03^{3}0 \leftarrow 00^{0}0$ BAND OF $^{12}C {^{16}}0_{2}$
Loading...
Date
1984
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Ohio State University
Abstract
Lines of the $03^{3}0 \leftarrow 00^{0}0$ ``forbidden'' band of $^{12}C {^{16}}0_{2}$ have been identified in the $2000-cm^{-1}$ region of long-path, $0.01-cm^{-1}$ resolution laboratory absorption spectra recorded with the Fourier transform spectrometer in the McMath solar telescope at the National Solar Observatory. The spectral data were obtained at room temperature and with pressures less than 10 Torr of natural $CO_{2}$. The $03^{3}0 \leftarrow 00^{0}0$ band has detectable intensity because of $\Delta \ell = 2$ Fermi interactions between the $03^{3}0$ upper level and the nearby $(11^{1}0)_{I}$ and $(11^{1}0)_{II}$ levels. Intensities of 8 P-branch lines (P24-P52), 9 Q-branch lines (Q24-Q42) and 1 R-branch line (R48) have been measured using a non-linear least squares spectral fitting technique. The strongest lines occur in the P branch and have intensities of $0.11 \times 10^{-25} cm^{-1} /molecule-cm^{-2}$ at 296 K. The measured intensities have been analyzed with an F-factor expression derived for this $case^{1}$ In terms of the total sample pressure, the band intensity is $0.194 \pm 0.008 \times 10^{-30} cm^{-1} /molecule-cm^{-2}$ at 296 K. The coefficient in the F factor is analogous to the Coriolis coefficient $\xi$ and has been determined to be $-0.0413 \pm 0.0015$. As expected by theory, its value is very close to that of $\xi$ for the related $(11^{1}0)_{I} \leftarrow 00^{0}0$ band.
Description
$^{1}$ R.A. Toth, Jet Propulsion Laboratory, private communications, 1984. Research at the College of William and Mary was supported by NASA Grant NCC 1-43.
Author Institution: Department of Physics, College of William and Mary; NASA Langley Research Center, Mail Stop 401A
Author Institution: Department of Physics, College of William and Mary; NASA Langley Research Center, Mail Stop 401A