J/A+A/431/143 Field horizontal-branch stars in the Galaxy (Christlieb+, 2005)
The stellar content of the Hamburg/ESO survey. III. Field horizontal-branch
stars in the Galaxy
Christlieb N., Beers T.C., Thom C., Wilhelm R., Rossi S., Flynn C.,
Wisotzki L., Reimers D.
<Astron. Astrophys. 431, 143 (2005)>
=2005A&A...431..143C 2005A&A...431..143C
ADC_Keywords: Stars, horizontal branch ; Positional data; Photometry, UBV;
Colors
Keywords: stars: horizontal-branch - Galaxy: halo -
Galaxy: kinematics and dynamics - surveys - methods: statistical
Abstract:
We present a sample of 8321 candidate Field Horizontal-Branch (FHB)
stars selected by automatic spectral classification in the digital
data base of the Hamburg/ESO objective-prism survey. The stars are
distributed over 8225 square degrees of the southern sky, at
|b|≳30°. The average distance of the sample, assuming that they
are all FHB stars, is 9.8kpc, and distances of up to ∼30kpc are
reached. Moderate-resolution spectroscopic follow-up observations and
$UBV$ photometry of 125 test sample stars demonstrate that the
contamination of the full candidate sample with main-sequence A-type
stars is <16%, while it would be up to 50% in a flux-limited sample at
high galactic latitudes. Hence more than ∼6800 of our FHB candidates
are expected to be genuine FHB stars. The candidates are being used as
distance probes for high-velocity clouds and for studies of the
structure and kinematics of the Galactic halo.
Description:
Table A.1 contains photometry (UBV, c1), and Balmer line equivalent width
sums, as derived directly from HES spectra, as well as coordinates of the
8321 candidate field horizontal-branch stars.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tabla1.dat 66 8321 The Field Horizontal-Branch (FHB) star sample
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Byte-by-byte Description of file: tabla1.dat
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Bytes Format Units Label Explanations
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2- 3 A2 --- --- [HE]
5- 14 A10 --- HEname HE designation (based on 1950 position)
16- 17 I2 h RAh Right ascension (J2000.0)
19- 20 I2 min RAm Right ascension (J2000.0)
22- 25 F4.1 s RAs Right ascension (J2000.0)
27 A1 --- DE- Declination sign (J2000.0)
28- 29 I2 deg DEd Declination (J2000.0)
31- 32 I2 arcmin DEm Declination (J2000.0)
34- 35 I2 arcsec DEs Declination (J2000.0)
37- 39 I3 --- Field ? ESO-SERC field number (1)
41- 44 F4.1 mag Bmag ? B magnitude (1)
46- 50 F5.2 mag B-V B-V colour
52- 56 F5.2 mag U-B U-B colour
58- 61 F4.2 mag c1 Stroemgren c1 index
63- 66 F4.1 0.1nm Wbal Sum of equivalent widths of Hbeta,
Hgamma and Hdelta
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Note (1): no photometric sequence is available in field #891.
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History:
* 11-Feb-2005: Original version
* 01-May-2005: B magnitude (31.3) of HE 0301-5342 suppressed
Acknowledgements: Norbert Christlieb, st4b321(at)hs.uni-hamburg.de
(End) N. Christlieb [Hamburger Sternwarte, Germany] 11-Feb-2005