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J/AJ/117/2329  Spectroscopy of hot stars in the halo. III   (Wilhelm+, 1999)
Spectroscopy of hot stars in the galactic halo. III. Analysis of a large
sample of field horizontal-branch and other A-type stars
    Wilhelm R., Beers T.C., Sommer-Larsen J., Pier J.R., Layden A.C.,
    Flynn C., Rossi S., Christensen P.R.
   <Astron. J. 117, 2329 (1999)>
   =1999AJ....117.2329W
ADC_Keywords: Abundances, [Fe/H] ; Photometry, UBV ; Stars, horizontal branch

Keywords: Galaxy: halo - stars: horizontal-branch - stars: Population II


Abstract:
    We present results from an analysis of medium-resolution spectroscopy
    and UBV photometry for a sample of 1121 A-type stars in the halo (and
    disk) of the Galaxy. A previously developed calibration technique is
    used to assign estimates of effective temperature, surface gravity,
    and stellar metal abundance, as parametrized by [Fe/H]. Radial
    velocities are reported with an accuracy of ∼10 km.s-1. Distance
    estimates are obtained for the stars with well-determined luminosity
    classes. Note that although we refer to "A-type" stars, which dominate
    the present sample, the present data set includes roughly 100 stars of
    later spectral types, as a result of the temperature range we have
    chosen to explore in this paper (6000 K ≤ Teff ≤ 10,000 K).

File Summary:

       FileName      Lrecl  Records   Explanations

ReadMe            80        .   This file
table1.dat       108     1121   Observed properties of the program sample
table2a.dat       83      140   Physical parameters for the Am/Ap subsample
table2b.dat       83      444   Physical parameters for the FHB subsample
table2c.dat       83      416   Physical parameters for the A V subsample
table2d.dat       83      121   Physical parameters for the FHB/A subsample
table3.dat        30       19   Known variable stars
tablea1.dat       52       58   Additional photometry for hot star candidates
tableb1.dat       45       81   Program stars with duplicate HK survey
                             identifications


See also:
  J/AJ/87/1515    : UBV photometry of AB stars in halo (Pier, 1982)
  J/ApJS/53/791   : Spectroscopy of AB stars in halo (Pier, 1983)
  J/AJ/90/2089    : Stars of very low metal abundance. (Beers+, 1985)
  J/PASP/102/1392 : UBV photometry from HK survey. (Doinidis+ 1990)
  J/PASP/103/973  : Photoelectric UBV from HK survey. (Doidinis+ 1991)
  J/ApJS/76/1001  : UBV photometry of HK survey stars (Preston+, 1991)
  J/AJ/103/267    : Spectrocopy of hot stars in galactic halo (Beers+ 1992)
  J/AJ/103/1987   : Stars of very low metal abundance (Beers+ 1992)
  J/AJ/108/268    : HK survey emission-line candidates positions (Beers+ 1994)
  J/AJ/108/538    : Metal-poor MS stars UBV photometry (Preston+ 1994)
  J/AJ/112/1188   : HK survey emission-line candidates (Beers+ 1996)
  J/ApJS/123/639  : UBV photometry of metal-weak candidates (Norris+, 1999)


Byte-by-byte Description of file: table1.dat

   Bytes Format Units   Label     Explanations

   1- 13  A13   ---     BPS       Star Name (field-number)
      15  A1    ---     f_BPS     [ab] Flag indicating new photometry (1)
  19- 20  I2    h       RAh       Right Ascension (B1950)
  22- 23  I2    min     RAm       Right Ascension (B1950)
  25- 28  F4.1  s       RAs       Right Ascension (B1950)
      30  A1    ---     DE-       Sign of the Declination (B1950)
  31- 32  I2    deg     DEd       Declination (B1950)
  34- 35  I2    arcmin  DEm       Declination (B1950)
  37- 38  I2    arcsec  DEs       Declination (B1950)
  40- 44  F5.2  mag     Vmag      V band magnitude
  46- 50  F5.2  mag     B-V       The B-V color
  55- 59  F5.2  mag     U-B       ? The U-B color
  61- 65  F5.2  mag     E(B-V)    The B-V reddening
  71- 74  F4.1  0.1nm   EqWK      ? Equivalent width of the CaII K line
  76- 79  F4.1  0.1nm   Ddelta    Line width of Hδ at 20% below the
                                   local continuum level
  81- 84  F4.1  0.1nm   Dgamma    Line width of Hγ at 20% below the
                                   local continuum level
  87- 90  I4    km/s    Vhelio    Heliocentric radial velocity
      92  A1    ---     u_Vhelio  Indicates an uncertain radial velocity
      95  A1    ---     Obs1      Observatory's code where data was obtained (2)
      97  A1    ---     Obs2      Second observatory's code where data was
                                   obtained (2)
      99  A1    ---     Obs3      Third observatory's code where data was
                                   obtained (2)
 101-108  A8    ---     Class     MK Stellar classification

Note (1):
    a = New CTIO photometry
    b = New Siding Spring Observatory photometry by Norris, Ryan, & Beers
        (1999ApJS..123..639N)
Note (2):
    E = European Southern Observatory
    H = Beers et al. (1992AJ....103..267B)
    K = Kitt Peak National Observatory
    L = Lowell observatory


Byte-by-byte Description of file: table2?.dat

   Bytes Format Units    Label   Explanations

   1- 13  A13   ---      BPS     Star name
  16- 20  I5    K        Teff    Effective temperature
      22  A1    ---      u_Teff  Uncertain Teff flag
  26- 28  F3.1  [cm/s2]  log(g)  The log of the surface gravity
      30  A1    ---    u_log(g)  Uncertain log(g) flag
  36- 39  F4.1  [Sun]    Wk      ? The [Fe/H] abundance from the CaII
                                   K-line equivalent width technique
  43- 46  F4.1  [Sun]    CTA     ? The [Fe/H] abundance from the CaII
                                   K template matching technique
  50- 53  F4.1  [Sun]    MTA     ? The [Fe/H] abundance from the metallic-
                                   line region template matching procedure
      55  A1    ---      u_MTA   Uncertain MTA flag
  57- 60  F4.1  [Sun]    AVG     ? Average [Fe/H] abundance from best estimate
      62  A1    ---      u_AVG   Abundance obtained from Lowell data
  65- 67  F3.1  [Sun]    Diff    ? Absolute difference between the two most
                                   consistent metallicity indicators
  71- 74  F4.1  kpc      Dist    ? Distance estimate
  79- 83  A5    ---      Text    Comment on star (1)

Note (1): abbreviations are:
     r = Noted in present analysis as a candidate variable star
    rr = noted by Preston et al. (1991ApJS...76.1001P) as a candidate
         variable star
    RR = noted in Table 3 as an RR Lyrae variable
     B = classified by Preston et al. (J/AJ/108/538) as a BMP star


Byte-by-byte Description of file: table3.dat

   Bytes Format Units   Label     Explanations

   1- 13  A13   ---     BPS       CS designation
  15- 23  A9    ---    OtherName  Other Name
  26- 30  A5    ---     Class     Class


Byte-by-byte Description of file: tablea1.dat

   Bytes Format Units   Label     Explanations

   1- 13  A13   ---     BPS       CS designation
  15- 16  I2    h       RAh       Right ascension (1950.0)
  18- 19  I2    min     RAm       Right ascension (1950.0)
  21- 24  F4.1  s       RAs       Right ascension (1950.0)
      26  A1    ---     DE-       Declination sign (1950.0)
  27- 28  I2    deg     DEd       Declination (1950.0)
  30- 31  I2    arcmin  DEm       Declination (1950.0)
  33- 34  I2    arcsec  DEs       Declination (1950.0)
  36- 40  F5.2  mag     Vmag      V magnitude
  42- 46  F5.2  mag     B-V       B-V colour index
  48- 52  F5.2  mag     U-B       U-B colour index


Byte-by-byte Description of file: tableb1.dat

   Bytes Format Units   Label     Explanations

   1- 13  A13   ---     BPS       Catalogued star name
  17- 29  A13   ---     BPS1      Alternate name 1
  33- 45  A13   ---     BPS2      Alternate name 2


History:
    From AJ electronic edition.

References:
    (Paper II) Wilhelm+ 1999AJ....117.2308W
    (Paper I) Beers+ 1992AJ....103..267B
(End)                                          Greg Schwarz [AAS]    25-Apr-2000