J/ApJ/711/1236 Equivalent width of H2 from FUSE (Jensen+, 2010)
Observational properties of rotationally excited molecular hydrogen in
translucent lines of sight.
Jensen A.G., Snow T.P., Sonneborn G., Rachford B.L.
<Astrophys. J., 711, 1236-1256 (2010)>
=2010ApJ...711.1236J 2010ApJ...711.1236J
ADC_Keywords: Equivalent widths ; Extinction ; Interstellar medium ;
Ultraviolet
Keywords: ISM: molecules - ultraviolet: ISM
Abstract:
The Far Ultraviolet Spectroscopic Explorer (FUSE) has allowed precise
determinations of the column densities of molecular hydrogen (H2) in
Galactic lines of sight with a wide range of pathlengths and
extinction properties. However, survey studies of lines of sight with
greater extinction have been mostly restricted to the low-J states
(lower total angular momentum) in which most molecular hydrogen is
observed. This paper presents a survey of column densities for the
molecular hydrogen in states of greater rotational excitation (J≥2)
in Galactic lines of sight with log N(H2)≳20. This study is
comprehensive through the highest excited state detectable in each
line of sight. J=5 is observed in every line of sight, and we detect
J=7 in four lines of sight, J=8 in one line of sight, and
vibrationally excited H2 in two lines of sight.
Description:
The spectra under examination are taken from the FUSE archives (the
Far Ultraviolet Spectroscopic Explorer operated from 1999 through
2007). We have selected a sample of 22 lines of sight from the FTCS
(FUSE Translucent Cloud Survey).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
sample.dat 63 22 Lines of sight: stellar and reddening data
(tables 1 and 2 of the paper)
ew.dat 32 3586 Measured equivalent widths (table 3 of the paper)
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See also:
VI/129 : The FUSE Observation Log (FUSE, 1999-2007)
J/ApJS/163/282 : Molecular hydrogen column densities (Wakker+, 2006)
http://astro.uchicago.edu/~dwelty/coldens.html : Online catalogue of ISM
column densities
Byte-by-byte Description of file: sample.dat
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Bytes Format Units Label Explanations
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1- 9 A9 --- Name Star name
11- 18 A8 --- SpType MK spectral type
20- 25 F6.2 deg GLON Galactic longitude
27- 32 F6.2 deg GLAT Galactic latitude
34- 37 I4 pc dist ? Distance
39 I1 --- r_dist ? Distance reference (1)
41- 44 F4.2 mag E(B-V) Color excess
46- 47 I2 --- r_E(B-V) E(B-V) reference (1)
49- 52 F4.2 mag Av V-band interstellar extinction AV
54- 55 I2 --- r_Av Av reference (1)
57- 60 F4.2 mag Rv V-band interstellar extinction
(RV=AV/E(B-V))
62- 63 I2 --- r_Rv Rv reference (1)
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Note (1): References as follows:
1 = From the DIBS database, http://dib.uiuc.edu/, values compiled by
L. M. Hobbs, spectroscopic distance modulus.
2 = Hipparcos value of 4σ significance or better.
3 = Savage et al. 1985, Cat. II/114.
4 = From the DIBS database, http://dib.uiuc.edu/, values compiled by
L. M. Hobbs, stellar association.
11 = Diplas & Savage 1994, Cat. J/ApJS/93/211.
12 = Rachford et al. 2002ApJ...577..221R 2002ApJ...577..221R; if AV, ref. (16) also applies.
13 = From the DIBS database, http://dib.uiuc.edu/, values by the DIBS team.
14 = Rachford et al. 2009ApJS..180..125R 2009ApJS..180..125R; if AV, ref. (16) also applies.
15 = Valencic et al. 2004ApJ...616..912V 2004ApJ...616..912V.
16 = Calculated through the definition RV=AV/EB-V using values from the
other two columns.
17 = RV not independently measured and is assumed to be the Galactic average
of 3.1.
18 = Neckel et al. 1980, Cat. II/62.
19 = Aiello et al. 1988, Cat. III/130.
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Byte-by-byte Description of file: ew.dat
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Bytes Format Units Label Explanations
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1- 9 A9 --- Name Star name
11- 18 F8.3 0.1nm lambda Wavelength of transition; in Angstroms
20 I1 --- J The J level of transition
22- 26 F5.1 10-13m EW ? Measured equivalent width (mÅ)
28- 32 F5.1 10-13m e_EW ? Uncertainty in measured equivalent width
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 05-Apr-2012