J/ApJ/757/46 Hot methane (CH4) line list (Hargreaves+, 2012)
Hot methane line lists for exoplanet and brown dwarf atmospheres.
Hargreaves R.J., Beale C.A., Michaux L., Irfan M., Bernath P.F.
<Astrophys. J., 757, 46 (2012)>
=2012ApJ...757...46H 2012ApJ...757...46H
ADC_Keywords: Atomic physics ; Line Profiles ; Spectra, infrared
Keywords: brown dwarfs; infrared: general; methods: laboratory; molecular data;
planetary systems; techniques: spectroscopic
Abstract:
We present comprehensive experimental line lists of methane (CH4) at
high temperatures obtained by recording Fourier transform infrared
emission spectra. Calibrated line lists are presented for the
temperatures 300-1400°C at twelve 100°C intervals spanning the
960-5000/cm (2.0-10.4µm) region of the infrared. This range
encompasses the dyad, pentad, and octad regions, i.e., all fundamental
vibrational modes along with a number of combination, overtone and hot
bands. Using our CH4 spectra, we have estimated empirical lower state
energies (Elow in cm-1) and our values have been incorporated into
the line lists along with line positions (ν in cm-1) and
calibrated line intensities (S' in cm/molecule). We expect our hot
CH4 line lists to find direct application in the modeling of
planetary atmospheres and brown dwarfs.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table6.dat 22 12 Line list summary (from erratum 2013, ApJ, 774, 89)
table8.dat 47 622085 The hot CH4 line list
(from erratum 2013, ApJ, 774, 89)
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See also:
J/ApJ/735/111 : NH3 line lists at high temperatures (Hargreaves+, 2011)
J/ApJ/714/476 : Complete spectrum of ethyl cyanide (Fortman+, 2010)
J/ApJ/708/1452 : Quadratic Fij force field in l-CH4- (Senent+, 2010)
Byte-by-byte Description of file: table6.dat
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Bytes Format Units Label Explanations
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1- 4 I4 degC T [300/1400] Temperature (°C)
(12values, step of 100°C)
6- 10 I5 --- Nobs [3255/39485] Number of observed lines
12- 16 I5 --- Nadd [9120/39613] Number of added HITRAN lines
18- 22 I5 --- Ntot [12375/79098] Total lines
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Byte-by-byte Description of file: table8.dat
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Bytes Format Units Label Explanations
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1- 4 I4 deg T [300/1400] Temperature (°C)
(12values, step of 100°C)
6- 17 F12.7 cm-1 sigma [968/4860] Wavenumber σ
19- 31 E13.8 cm Int Intensity in units of cm/molecule
33- 45 E13.8 cm-1 Elow [0/18133]?=-1 Empirical lower state energy
47 A1 --- Q Quality factor (1)
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Note (1): Quality factor as follows:
H = The line position, intensity and lower state energy has been inserted
from the HITRAN database.
1 = The lower state energy has been calculated from the intensities of a
line that appears in 10 or more spectra.
2 = The line appear in 6-9 spectra.
3 = The lower state energy has been determined from 3-5 spectra.
0 = The lower state energy could not be determined from the spectra
available; the line occurs in less than 3 spectra in total.
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 21-May-2014