HR: 0800h
AN: SA41A-1041 [Abstracts]
TI: Absolute Intensities of the OH Meinel bands in the Nightglow
AU: * Cosby, P C
EM: philip.cosby@sri.com
AF: Molecular Physics Lab, SRI International, Menlo Park, CA 94025
United States
AU: Slanger, T G
EM: tom.slanger@sri.com
AF: Molecular Physics Lab, SRI International, Menlo Park, CA 94025
United States
AB:
Flux-calibrated high resolution spectra of the night sky have been accumulated for
the spectral region of 314 - 1054 nm. The spectra are obtained from two sources: (a)
the ESI spectrograph on the Keck II telescope at Mauna Kea with a spectral resolution
of 6000 and a temporal resolution of 3000 seconds and (b) coadded spectra (1)
from the UVES spectrograph on the VLT (Kueyen) telescope at Cerro Paranal with a spectral
resolution of 50000. Emission from the OH X$^{2}\Pi$(v'=3-9) Meinel bands are prominent
in the spectra allowing absolute intensities to be measured for discrete rotational lines in
the main rotational branches for 16 vibrational bands in the ESI spectra ($\Delta$v = -6 to -3) and 20 vibrational
bands in the UVES spectrum ($\Delta$v = -7 to -3). Comparison of the band intensities to the earlier
photographic measurements of Krassovsky et al.(2) show a systematic deviation with wavelength
similar to that deduced by Adler-Golden(3). Several emission bands are observed from
most upper state vibrational levels. Comparisons of the band intensity ratios and the rotational
branch intensity ratios for these bands show systematic deviations from those calculated using
the existing sets of emission coefficients. Progress will be reported on the re-evaluation of
the dipole moment function (4) using the present absolute intensities to obtain an improved
set of OH emission coefficients.
This work was partially supported by NSF grant ATM-0139344.
(1) R. W. Hanuschik, Astron. Astrophys. {\bf 112}, 1157 (2003).
(2) V. I. Krassovsky et al., Planet. Space Sci. {\bf 9}, 883 (1962).
(3) S. Adler-Golden, J. Geophys. Res. {\bf 102}, 19969 (1997).
(4) D. D. Nelson et al., J. Chem. Phys. {\bf 93}, 7003 (1990).
DE: 0310 Airglow and aurora
SC: SPA-Aeronomy [SA]
MN: 2004 AGU Fall Meeting