J/PASP/115/22 Stellar parameters for 134 cool subdwarfs (Yong+, 2003)
A search for cool subdwarfs: stellar parameters for 134 candidates.
Yong D., Lambert D.L.
<Publ. Astron. Soc. Pac. 115, 22 (2003)>
=2003PASP..115...22Y 2003PASP..115...22Y
ADC_Keywords: Stars, subdwarf ; Space velocities ; Effective temperatures ;
Abundances, [Fe/H]
Abstract:
The results of a search for cool subdwarfs are presented. Kinematic
(U, V, and W) and stellar parameters (Teff, logg, [Fe/H], and Vturb)
are derived for 134 candidate subdwarfs based on high-resolution
spectra. The observed stars span 4200K<Teff<6400K and
-2.70<[Fe/H]<0.25 including only eight giants (logg<4.0). Of the
sample, 100 stars have MgH bands present in their spectra. The targets
were selected by their large reduced proper motion, by the offset from
the solar-metallicity main sequence, or from the literature. We
confirm the claims made by Ryan (1989, Cat. J/AJ/98/1693) that the
NLTT catalog is a rich source of subdwarfs and verify the success of
the reduced proper-motion constraint in identifying metal-poor stars.
Description:
Table 1 contains the list of candidates observed at McDonald
Observatory on the 2.7m Harlan J. Smith telescope and on the 9.2m
Hobby-Eberly telescope (HET) between 1999 November and 2002 April. The
2.7m data were obtained using the cross-dispersed echelle spectrometer
(Tull et al., 1995PASP..107..251T 1995PASP..107..251T) at the coude f/32.5 focus with a
resolving power of either 30000 or 60000. The detector was a
Tektronix CCD with 24µm2 pixels in a 2048x2048 format. For this
setting, the spectral coverage was from 3800 to 8900Å with gaps
between the orders beyond 5800Å. The HET data were taken with the
Upgraded Fiber Optic Echelle spectrograph (Harlow et al.,
1996AAS...189.4207H 1996AAS...189.4207H) at a resolving power of 11000 on a 1024x1024
CCD. The spectral coverage was from 4500 to 9000Å with gaps between
the orders beyond 7300Å.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 112 134 Basic data and derived parameters for objects
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See also:
I/98 : NLTT Catalogue (Luyten, 1979)
I/239 : The Hipparcos and Tycho Catalogues (ESA 1997)
I/238 : Yale Trigonometric Parallaxes, 4th Edition (van Altena+ 1995)
J/AJ/98/1693 : UBVRI photometry of NLTT stars (Ryan 1989)
J/AJ/107/2240 : Proper motion stars survey. XII. (Carney+, 1994)
J/AJ/113/806 : M-Subdwarfs (Gizis 1997)
J/A+AS/117/227 : Dwarf effective temperatures (Alonso+ 1996)
J/MNRAS/325/931 : Metal-poor subdwarfs in the Hipparcos catalog (Reid+, 2001)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 15 A15 --- Name Name
17- 18 I2 h RAh Right ascension (J2000.0)
20- 21 I2 min RAm Right ascension (J2000.0)
23- 24 I2 s RAs Right ascension (J2000.0)
26 A1 --- DE- Declination sign (J2000.0)
27- 28 I2 deg DEd Declination (J2000.0)
30- 31 I2 arcmin DEm Declination (J2000.0)
33- 34 I2 arcsec DEs Declination (J2000.0)
36- 40 I5 --- SpRes Resolving power (1)
42- 45 I4 K Teff Effective temperature
47- 51 F5.2 [Sun] [Fe/H] Metallicity
53- 56 F4.2 [cm/s2] logg Surface gravity
58- 60 F3.1 km/s Vturb Turbulence velocity
62- 65 I4 km/s UVel LSR U velocity
67- 69 I3 km/s e_UVel rms uncertainty on Uvel
71- 75 I5 km/s VVel LSR V velocity
77- 80 I4 km/s e_VVel rms uncertainty on VVel
82- 85 I4 km/s WVel LSR W velocity
87- 89 I3 km/s e_WVel rms uncertainty on WVel
91- 93 A3 --- Col Luyten colour
95-107 A13 --- Source References (3)
110 A1 --- n_Source [b-d] Individual Note (2)
112 A1 --- Mol [Y/N] Molecular features ?
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Note (1): HET data taken with R=11000; 2.7m data taken with R=30000 and 60000
Note (2): Individual notes as follows:
b = Star chosen from Carney et al., 1994, Cat. J/AJ/107/2240 and
Alonso et al., 1996, Cat. J/A+AS/117/227,
but also in NLTT, Cat. I/98) catalog.
c = Star chosen from Alonso et al. 1996, Cat. J/A+AS/117/227;
not in NLTT, Cat. I/98) catalog.
d = Star chosen from Carney et al., 1994, Cat. J/AJ/107/2240,
but also in NLTT, Cat. I/98) catalog.
Note (3): References as follows:
AAM96 = Alonso et al., 1996, Cat. J/A+AS/117/227
CLLA94 = Carney et al., 1994, Cat. J/AJ/107/2240
FJ98 = Fuchs & Jahreiss, 1998A&A...329...81F 1998A&A...329...81F
KF99 = Kotoneva & Flynn 1999, private communication;
Gizis97 = Gizis, 1997, Cat. J/AJ/113/806
HIP = Hipparcos, Cat. I/239, color-magnitude diagram;
RWMRKM01 = Reid et al., 2001, Cat. J/MNRAS/325/931
Yale = Yale, Cat. I/238, color-magnitude diagram.
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History:
From electronic version of the journal
(End) James Marcout, Patricia Bauer [CDS] 21-Feb-2003