J/A+A/571/A47 Extensive linelist of CH in stellar atmospheres (Masseron+, 2014)
CH in stellar atmospheres: an extensive linelist.
Masseron T., Plez B., Van Eck S., Colin R., Daoutidis I., Godefroid M.,
Coheur P.-F., Bernath P., Jorissen A., Christlieb N.
<Astron. Astrophys. 571, A47 (2014)>
=2014A&A...571A..47M 2014A&A...571A..47M
ADC_Keywords: Atomic physics
Keywords: molecular data - techniques: spectroscopic - stars: carbon
Abstract:
The advent of high-resolution spectrographs and detailed stellar
atmosphere modelling has strengthened the need for accurate molecular
data. Carbon-enhanced metal-poor (CEMP) stars spectra are interesting
objects with which to study transitions from the CH molecule. We
combine programs for spectral analysis of molecules and
stellar-radiative transfer codes to build an extensive CH linelist,
including predissociation broadening as well as newly identified
levels. We show examples of strong predissociation CH lines in CEMP
stars, and we stress the important role played by the CH features in
the Bond-Neff feature depressing the spectra of barium stars by as
much as 0.2∼magnitudes in the λ=3000-5500Å range. Because of
the extreme thermodynamic conditions prevailing in stellar atmospheres
(compared to the laboratory), molecular transitions with high energy
levels can be observed. Stellar spectra can thus be used to constrain
and improve molecular data.
Description:
Linelist for the CH molecules is presented. This includes the A-X,
B-X, and C-X electronic transitions up to the last observed
vibrational levels (i.e. v≥5 for the X and A states, v≥1 for
the B state, and v≥2 for the C state), with rotational levels up
to the dissociation energy as listed in Table 13.
Concerning the 13CH linelists, for the vibrational levels that could
not be observed but that exist for 12CH ( i.e. X2{Deltav=4 and
5, A2{Deltav=4 and 5, and C2{Sigma+ v=1 and 2), the
Born-Oppenheimer approximation from 12CH has been used to determine
the transitions. The X-X ro-vibrational transitions up to dissociation
are also included for both isotopologues.
The linelist is available on
http://www.astro.ulb.ac.be/~spectrotools/, and will be made available
through the VALD database.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table14.dat 156 102670 Linelist of the CH molecule
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See also:
J/MNRAS/425/34 : ExoMol line lists for BeH, MgH and CaH (Yadin+, 2012)
J/MNRAS/434/1469 : ExoMol line lists for SiO (Barton+, 2013)
J/MNRAS/437/1828 : ExoMol line list for HCN and HNC (Barber+, 2014)
J/MNRAS/440/1649 : ExoMol line lists for CH4 (Yurchenko+, 2014)
J/MNRAS/442/1821 : ExoMol line list for NaCl and KCl (Barton+, 2014)
Table 13: Equilibrium constants for 12CH
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Constant X2{PI} a3{SIGMA}- A2{DELTA} B2{SIGMA}- C2{SIGMA}+
De(cm-1) 29374.0 23349.6 16210.26 4731.57 7549.36
D00(cm-1) 27959.64
re(ÅA) 1.11981 1.0892 1.10366 1.16370 1.12777
Te 0.0 6024.40a 23148.7375 24642.425 31809.6428
ωe 2860.9238 3090.9 a 2923.3763 2255.07 2853.1724
ωexe 64.58180 102.17 a 90.2 223.2c 120.8564
ωeye 0.407275 --- -0.1917
ωeze -0.01980 --- -0.3892
Be 14.45924 15.364 b 14.88536 13.3818 14.56066
αe 0.53502 0.553b -0.591798 1.4828 0.56653
γe 0.001993 --- -0.047110 --- -0.08659
εe 0.000214 --- 0.00782
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Notes:
a: Constants taken from Kalemos et al. (1999, Journal of Chemical
Physics, 111, 9536)
b: Constants taken from Lie et al. (1973, J. Chem. Phys., 59, 1887).
c: value fixed according to Lie et al. (1973, J. Chem. Phys., 59, 1887)
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Byte-by-byte Description of file: table14.dat
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Bytes Format Units Label Explanations
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6- 18 F13.4 0.1nm lam.Air [2554/33376282] Wavelength of the transition
in air (Å)
21- 34 E14.7 --- gf ?=-999 Oscillator strength value
39- 49 F11.5 cm-1 Elow [14/33902] Energy of the lower level
52 I1 --- vl [0/6] Vibrational quantum number of lower level
55- 58 F4.1 --- J [0.5/49.5] Rotational angular momentum quantum
number of the lower level
61- 62 I2 --- Nl [0/49] Rotational angular momentum number
of the lower level
64 A1 --- syml [e/f] Symmetry of the lower level
70- 80 F11.5 cm-1 Eup [2738/57430] Energy of the upper level
83 I1 --- vu [0/5] Vibrational quantum number of upper level
86- 89 F4.1 --- Ju [0.5/49.5] Rotational angular momentum number
of the upper level
92- 93 I2 --- Nu [0/49] Rotational angular momentum number
of the upper level
95 A1 --- symu [e/f] Symmetry of the upper level
100-111 E12.7 s-1 gamrad Radiative broadening value
113-116 A4 --- mol Molecule: 12CH or 13CH
118-120 A3 --- trans Electronic states of the transition
123 A1 --- branch Branch of the transition (P,Q or R)
125-132 F8.5 cm-1 o-c [-1.7/1.3] Difference between measurement
and calculation
134-156 A23 --- Ref Reference of the measurement and comments (1)
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Note (1): References are:
Bembenek et al. (1997) = Bembenek et al., 1997,
Journal of Molecular Spectroscopy, 183, 1
Bernath et al. (1991) = Bernath et al., 1991,
Journal of Molecular Spectroscopy, 147, 16
Colin (2010) = Colin & Bernath, 2010,
Journal of Molecular Spectroscopy, 263, 120
Heimer (1932) = Heimer, T. 1932, Zeitschrift fur Physik, 78, 771
Herzberg & Johns (1969) = Herzberg & Johns, 1969, ApJ, 158, 399
Kepa et al. (1996) = Kepa et al., 1996,
Journal of Molecular Spectroscopy, 178, 189
Kumar et al. (1998) = Kumar et al., 1988, J. Chem. Phys., 109, 3824
Li et al. (1999) = Li & Lee, 1999, J. Chem. Phys., 111, 4942
Para et al. (1996) = Para, 1996,
Journal of Physics B Atomic Molecular Physics, 29, 5765
Ubachs et al. (1996) = Ubachs et al., 1986, J. Chem. Phys., 84, 3032
Zachwieja et al. (1995) = Zachwieja, 1995,
Journal of Molecular Spectroscopy, 170, 285
Zachwieja et al. (1997) = Zachwieja, 1997,
Journal of Molecular Spectroscopy, 182, 18
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Acknowledgements:
Thomas Masseron, tpm40(at)ast.cam.ac.uk
History:
* 06-Nov-2014: on-line version
* 16-Mar-2017: table14 corrected (from author)
(End) Patricia Vannier [CDS] 03-Oct-2014