J/A+A/606/A76 The ESO DIBs Large Exploration Survey (Cox+, 2017)
The ESO Diffuse Interstellar Bands Large Exploration Survey (EDIBLES).
I. Project description, survey sample, and quality assessment.
Cox N.L.J., Cami J., Farhang A., Smoker J., Monreal-ibero A., Lallement R.,
Sarre P.J., Marshall C.C.M., Smith K.T., Evans C.J., Royer P., Linnartz H.,
Cordiner M.A., Joblin C., van Loon J.T., Foing B.H., Bhatt N.H., Bron E.,
Elyajouri M., de Koter A., Ehrenfreund P., Javadi A., Kaper L.,
Khosroshadi H.G., Laverick M., Le Petit F., Mulas G., Roueff E., Salama F.,
Spaans M.
<Astron. Astrophys. 606, A76 (2017)>
=2017A&A...606A..76C 2017A&A...606A..76C (SIMBAD/NED BibCode)
ADC_Keywords: Surveys ; Extinction ; Interstellar medium
Keywords: ISM: lines and bands - ISM: clouds - ISM: molecules -
dust, extinction - stars: early-type - local interstellar matter
Abstract:
The carriers of the diffuse interstellar bands (DIBs) are largely
unidentified molecules ubiquitously present in the interstellar medium
(ISM). After decades of study, two strong and possibly three weak
near-infrared DIBs have recently been attributed to the C+60
fullerene based on observational and laboratory measurements. There is
great promise for the identification of the over 400 other known DIBs,
as this result could provide chemical hints towards other possible
carriers. In an effort to systematically study the properties of the
DIB carriers, we have initiated a new large-scale observational
survey: the ESO Diffuse Interstellar Bands Large Exploration Survey
(EDIBLES). The main objective is to build on and extend existing DIB
surveys to make a major step forward in characterising the physical
and chemical conditions for a statistically significant sample of
interstellar lines-of-sight, with the goal to reverse-engineer key
molecular properties of the DIB carriers. EDIBLES is a filler Large
Programme using the Ultraviolet and Visual Echelle Spectrograph at the
Very Large Telescope at Paranal, Chile. It is designed to provide an
observationally unbiased view of the presence and behaviour of the
DIBs towards early-spectral-type stars whose lines-of-sight probe the
diffuse-to-translucent ISM. Such a complete dataset will provide a
deep census of the atomic and molecular content, physical conditions,
chemical abundances and elemental depletion levels for each sightline.
Achieving these goals requires a homogeneous set of high-quality data
in terms of resolution (R∼70000-100000), sensitivity (S/N up to 1000
per resolution element), and spectral coverage (305-1042nm), as well
as a large sample size (100+ sightlines). In this first paper the
goals, objectives and methodology of the EDIBLES programme are
described and an initial assessment of the data is provided.
Description:
We constructed a statistically representative survey sample that
probes a wide range of interstellar environment parameters including
reddening E(B-V), visual extinction AV, total-to-selective
extinction ratio RV, and molecular hydrogen fraction fH2.
EDIBLES provides the community with optical (∼305-1042nm) spectra at
high spectral resolution (R∼70000 in the blue arm and 100000 in the
red arm) and high signal-to-noise (S/N; median value ∼500-1000), for
a statistically significant sample of interstellar sightlines. Many of
the >100 sightlines included in the survey already have auxiliary
available ultraviolet, infrared and/or polarisation data on the dust
and gas components.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablea1.dat 96 96 Targets observed for EDIBLES
tablea2.dat 96 18 Observations planned to complete the EDIBLES sample
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Byte-by-byte Description of file: tablea1.dat tablea2.dat
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Bytes Format Units Label Explanations
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1- 9 A9 --- Name Star name
11- 12 I2 h RAh Right ascension (J2000)
14- 15 I2 min RAm Right ascension (J2000)
17- 20 F4.1 s RAs Right ascension (J2000)
22 A1 --- DE- Declination sign (J2000)
23- 24 I2 deg DEd Declination (J2000)
26- 27 I2 arcmin DEm Declination (J2000)
29- 32 F4.1 arcsec DEs Declination (J2000)
34- 56 A23 --- SpType MK spectral type
58- 60 A3 --- r_SpType Reference for spectral type (1)
62- 65 F4.2 mag E(B-V) ?=- Interstellar reddenning (2)
67- 70 F4.2 --- RV ?=- Total-to-selective extinction ratio
72- 75 F4.2 mag AV ?=- Visual extinction
77- 79 A3 --- r_AV Reference for AV (1)
81- 85 F5.2 [cm-2] logNHI ?=- HI column density (3)
87- 91 F5.2 [cm-2] logNH2 ?=- H2 column density (3)
93- 96 F4.2 --- fH2 ?=- Molecular hydrogen fraction
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Note (1): References as follows:
A69 = Abt & Morgan, 1969AJ.....74..813A 1969AJ.....74..813A
C69 = Cowley et al., 1969AJ.....74..375C 1969AJ.....74..375C
E05 = Evans et al., 2005R, Cat. J/A+A/437/467
F57 = Feast et al., 1957MmRAS..68....1F 1957MmRAS..68....1F
G01 = Gray et al., 2001, Cat. J/AJ/121/2148
G68 = Guetter, 1968PASP...80..197G 1968PASP...80..197G
G77 = Garrison et al., 1977ApJS...35..111G 1977ApJS...35..111G
G94 = Garrison & Gray, 1994, Cat. J/AJ/107/1556
H13 = Holberg et al., 2013, Cat. J/MNRAS/435/2077
H56 = Hiltner, 1956, Cat. J/ApJS/2/389
H69 = Hiltner et al., 1969ApJ...157..313H 1969ApJ...157..313H
H73 = Humphreys, 1973A&AS....9...85H 1973A&AS....9...85H
H78 = Houk, 1978, Cat. III/51
H82 = Hendry, 1982PASP...94..169H 1982PASP...94..169H
L06 = Levenhagen & Leister 2006)
L68 = Lesh, 1968ApJS...17..371L 1968ApJS...17..371L, Cat. III/23
L75 = Levato, 1975A&AS...19...91L 1975A&AS...19...91L
L76 = Levato & Abt, 1976PASP...88..712L 1976PASP...88..712L
M50 = Morgan & Roman, 1950ApJ...112..362M 1950ApJ...112..362M
M55 = Morgan et al., 1955ApJS....2...41M 1955ApJS....2...41M
M73 = Morgan & Keenan, 1973ARA&A..11...29M 1973ARA&A..11...29M
M95 = Massey et al., 1995, Cat. J/ApJ/454/151
O59 = Osawa, 1959ApJ...130..159O 1959ApJ...130..159O
P98 = Parsons & Ake, 1998, Cat. J/ApJS/119/83
R09 = Renson & Manfroid, 2009A&A...498..961R 2009A&A...498..961R, Cat. III/260
S11 = Sota et al., 2011ApJS..193...24S 2011ApJS..193...24S, Cat. III/274
S14 = Sota et al., 2014ApJS..211...10S 2014ApJS..211...10S, Cat. III/274
S52 = Sharpless, 1952ApJ...116..251S 1952ApJ...116..251S
S56 = Stebbins & Kron, 1956ApJ...123..440S 1956ApJ...123..440S, classification originally
from W. W. Morgan
S71 = Schild & Chaffee, 1971ApJ...169..529S 1971ApJ...169..529S
S99 = Steele et al., 1999A&AS..137..147S 1999A&AS..137..147S
V04 = Valencic et al., 2004ApJ...616..912V 2004ApJ...616..912V),
Fitzpatrick & Massa (2007, Cat. J/ApJ/663/320)
W03 = Wegner, 2003, Cat. J/AN/324/219
W71 = Walborn, 1971ApJS...23..257W 1971ApJS...23..257W
W76 = Walborn, 1976ApJ...205..419W 1976ApJ...205..419W
Note (2): The interstellar reddening, E(B-V), was computed from (B-V)J colours
(taking the average from Tycho-2 and Simbad B-V colours; where Tycho-2 colours
were converted to Johnson colours; Mamajek et al. (2002, Cat. J/AJ/124/1670)
and the published spectral classifications, adopting intrinsic colours from
Fitzgerald (1970A&A.....4..234F 1970A&A.....4..234F).
Note (3): From Jenkins (2009, Cat. J/ApJ/700/1299).
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 18-Jan-2018