J/A+A/484/721 HES survey. IV. Candidate metal-poor stars (Christlieb+, 2008)
The stellar content of the Hamburg/ESO survey.
IV. Selection of candidate metal-poor stars.
Christlieb N., Scharck T., Frebel A., Beers T.C., Wisotzki L., Reimers D.
<Astron. Astrophys. 484, 721 (2008)>
=2008A&A...484..721C 2008A&A...484..721C
ADC_Keywords: Surveys ; Stars, metal-deficient ; Photometry, infrared
Keywords: surveys - Galaxy: halo - Galaxy: stellar content - Galaxy: formation -
Galaxy: evolution - stars: population II
Abstract:
We present the quantitative methods used for selecting candidate
metal-poor stars in the Hamburg/ESO objective-prism survey (HES).
The selection is based on the strength of the CaII K line, B-V colors
(both measured directly from the digital HES spectra), as well as J-K
colors from the 2 Micron All Sky Survey. The KP index for CaII K can
be measured from the HES spectra with an accuracy of 1.0Å, and a
calibration of the HES B-V colors, using CCD photometry, yields a
1-sigma uncertainty of 0.07mag for stars in the color range
0.3<B-V<1.4.
Description:
This catalog contains information on the 20,271 candidate metal-poor
stars selected in the Hamburg/ESO objective-prism survey (HES) by
quantitative criteria (TableA1 = hescan.dat), and the results of a
cross-identification of these candidates with lists of candidates
or confirmed metal-poor stars generated by previous surveys
(TableA2 = crossid.dat).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
hescan.dat 141 20271 HES metal-poor candidates (table A1)
crossid.dat 66 276 Cross-identification with other surveys (table A2)
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See also:
J/A+A/375/366 : Carbon stars from the Hamburg/ESO survey (Christlieb+, 2001)
J/A+A/431/143 : Field horizontal-branch stars in the Galaxy (Christlieb+, 2005)
Byte-by-byte Description of file: hescan.dat
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Bytes Format Units Label Explanations
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1- 2 A2 --- --- [HE]
4- 12 A9 --- HE HE designation (HE HHMM-DDMM)
14- 15 A2 --- --- [HE]
16- 33 A18 --- HESid Unique HES identifier (HENNNNNNmNNNNNNbNNNN)
35- 36 I2 h RAh Right ascension (J2000)
38- 39 I2 min RAm Right ascension (J2000)
41- 44 F4.1 s RAs Right ascension (J2000)
46 A1 --- DE- Declination sign (J2000)
47- 48 I2 deg DEd Declination (J2000)
50- 51 I2 arcmin DEm Declination (J2000)
53- 54 I2 arcsec DEs Declination (J2000)
56- 58 I3 --- Field ESO-SERC field number
60- 65 A6 --- Type Object type (stars or bright)
67- 70 F4.1 mag Bmag Photographic B magnitude (from HES)
72- 75 F4.2 mag E(B-V) Color excess
77- 80 F4.2 mag (B-V)0 De-reddened B-V color index
82- 86 F5.2 mag (J-K)0 ? De-reddened J-K color index
88- 92 F5.2 mag (V-K)0 ? De-reddened V-K color index
94- 95 I2 --- S/N(B) Average S/N of HES spectrum in BJ band
97- 98 I2 --- S/N(Ca) Average S/N of HES spectrum in Ca H and K
region (390-400nm)
100-103 F4.1 0.1nm KP KP index (CaII line) measured in HES spectrum
105-108 F4.1 0.1nm e_KP 1-σ uncertainty of KP index
111-115 F5.1 0.1nm GP GP index (CH G-band) measured in HES spectrum
117 I1 --- f1 [0,1] KP/(B-V)0 selection flag
119 I1 --- f2 [0,1] KP/(J-K)0 selection flag
121 I1 --- f3 [0,1] Ca K non-detection selection flag
123-126 A4 --- Class Candidate class (mpca, unid, mpcb or mpcc) (1)
128-131 F4.1 --- [Fe/H]K ? Estimate of Fe based on (B-V)0 and KPHES
133-136 F4.1 --- [Fe/H]R ? Estimate of Fe abundance based on (J-K)0
and KPHES
138-141 F4.1 --- [C/Fe]R ? Estimate of C abundance, based on GPHES
and KPHES
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Note (1): Classes are defined as follows:
mpca = a the spectrum clearly shows no CaII K line;
unid = it is unclear if a CaII K line is visible in the spectrum or not;
mpcb = a weak CaII K line is visible;
mpcc = a significant CaII K line appears against the continuum.
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Byte-by-byte Description of file: crossid.dat
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Bytes Format Units Label Explanations
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1- 2 A2 --- --- [HE]
3- 20 A18 --- HESid Unique HES identifier (HENNNNNNmNNNNNNbNNNN)
22- 23 A2 --- --- [HE]
25- 33 A9 --- HE HE designation (HE HHMM-DDMM)
35- 45 A11 --- BPS CS/BS identifier (BPS AA NNNNN-NNNN in Simbad)
47- 66 A20 --- ONames Other names
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Acknowledgements:
Norbert Christlieb, norbert(at)astro.uu.se
References:
Christlieb et al., Paper I 2001A&A...366..898C 2001A&A...366..898C
Christlieb et al., Paper II 2001A&A...375..366C 2001A&A...375..366C, Cat. J/A+A/375/366
Christlieb et al., Paper III 2005A&A...431..143C 2005A&A...431..143C, Cat. J/A+A/431/143
(End) Norbert Christlieb [Uppsala Univ.], Patricia Vannier [CDS] 25-Mar-2008