J/ApJ/690/L122 SiS line list (Cami+, 2009)
The detection of infrared SiS bands in spectra of S stars.
Cami J., Sloan G.C., Markwick-Kemper A.J., Zijlstra A.A.,
Bauschlicher C.W. Jr, Matsuura M., Decin L., Hony S.
<Astrophys. J. 690, L122 (2009)>
=2009ApJ...690L.122C 2009ApJ...690L.122C
ADC_Keywords: Atomic physics
Keywords: infrared: stars - molecular data - stars: AGB and post-AGB -
stars: atmospheres -
Abstract:
We present Spitzer spectra of S stars, which are cool evolved stars
with a C/O ratio near unity, some of which have enhanced s-process
abundances. We present the detection of a strong and unusual band
in the mid-infrared, at 13um, within the N-band window. Using
quantum-chemically calculated line lists, and model spectra, we
identify this band as the fundamental rovibrational band of SiS.
Detection of the overtone band at 6.7um confirms the identification
Fitting the line profile shows that the molecule is located in
relatively cool layers, at T∼1500K. We discuss these results in the
context of chemical equilibrium models. The observed strength of these
bands in the cool S stars makes them a promising observational
diagnostic tool for studying the atmospheres of brown dwarfs and
exoplanets.
Description:
We present an infrared line list for the ro-vibrational transitions of
SiS. Included are the fundamental and several overtone bands (up to
Δv=4) for vibrational levels up to v=13 and rotational levels
up to J=350. This line list contains the transition frequency, the
lower state energy, the Einstein A value and the relevant vibrational
and rotational quantum numbers.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
sis.dat 57 31590 SiS line list
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Byte-by-byte Description of file: sis.dat
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Bytes Format Units Label Explanations
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2- 12 F11.6 cm-1 sigma Transition frequency
15- 26 F12.6 cm-1 E Lower state energy
28- 41 E14.8 s-1 A Einstein transition probability (A-value)
44- 45 I2 -- vl Lower state vibrational quantum number
48- 49 I2 -- vu Upper state vibrational quantum number
51- 53 I3 -- Jl Lower state angular momentum quantum number
55- 57 I3 -- Ju Upper state angular momentum quantum number
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Acknowledgements:
Jan Cami, jcami(at)uwo.ca
(End) Jan Cami [UWO], Patricia Vannier [CDS] 13-Jan-2009