Astronomical Data Center

ADCADC/CDS Standard Document for Catalog:
/catalogs/2/2187/

The following is the "ReadMe" document that describes this ADC catalog. You can access the files described here in three ways:

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II/187               30 Doradus OB Associations                    (Parker 1992)
================================================================================
30 Doradus in the Large Magellanic Cloud: The Stellar Content and
Initial Mass Function
      Parker J.W.
      <Publ. Astron. Soc. Pac. 104, 1107 (1992)>
      =1992PASP..104.1107P          (SIMBAD/NED RefCode)
================================================================================
ADC_Keywords: Magellanic Clouds; Clusters, open; Photometry, UBV

Abstract:
    Johnson UBV photometry is presented for 2395 stars in the OB
    associations of 30 Doradus in the Large Magellanic Cloud. The CCD
    fields cover an area of 50 square arcminutes in the central
    region. The entire catalog (exclusive of the dense core cluster R
    136) is photometrically complete to V = B = 18 mag and U = 17 mag,
    although the completeness magnitudes are fainter for regions with
    less nebular contamination.

Introduction:
    These data have been reduced from 39 CCD frames (with short,
    medium, and long exposure times ranging from 3 to 1000 seconds)
    using the photometry program DAOPHOT written by Peter Stetson
    (1987, PASP, 99, 191). The photometric errors listed in these
    tables are the errors derived by DAOPHOT using the relative
    magnitude of the star on the CCD and the goodness of the fit of
    the point spread function. Most stars appear on more than one CCD
    frame per filter, and their resulting tabulated magnitudes are the
    averages of the individual measurements inversely weighted by the
    squares of their errors.

    The stars in these tables are from two regions: the central region
    and a non-overlapping northern region. The latter are designated
    by four digit numbers starting with 9. The X,Y coordinates are the
    positions relative to the northwestern-most corner of each region.
    The celestial coordinates have been calculated using full plate
    solutions of a few dozen stars measured on ESO sky survey plates
    and the X,Y coordinates from the catalogs.

File Summary:
--------------------------------------------------------------------------------
 FileName    Lrecl    Records      Explanations
--------------------------------------------------------------------------------
ReadMe          80         .       This file
tbl4-5.dat     101      2395       Positional and photometric data
tbl11-12.dat   125       302       Spectroscopic data
--------------------------------------------------------------------------------

Byte-by-byte Description of file: tbl4-5.dat
--------------------------------------------------------------------------------
   Bytes Format   Units    Label    Explanations
--------------------------------------------------------------------------------
   3-  6  I4      ---      Num     *Running number
   9- 10  I2      h        RAh      Right ascension 2000
  12- 13  I2      min      RAm      Right ascension 2000
  15- 18  F4.1    s        RAs      Right ascension 2000
      21  A1      ---      DE-      Declination sign 2000
  22- 23  I2      deg      DEd      Declination 2000
  25- 26  I2      arcmin   DEm      Declination 2000
  28- 29  I2      arcsec   DEs      Declination 2000
  33- 38  F6.2    pix      X       *X position
  41- 47  F7.2    pix      Y       *Y position
  51- 56  F6.3    mag      V       *V magnitude
  60- 65  F6.3    mag      B-V     *B-V color
  69- 74  F6.3    mag      U-B     *U-B color
  79- 83  F5.3    mag      e_V      V accuracy
  88- 92  F5.3    mag      e_B-V    B-V accuracy
  97-101  F5.3    mag      e_U-B   *U-B accuracy
--------------------------------------------------------------------------------
Note on U-B: 99.000 indicates no value for U-B
Note on e_U-B: 9.000 indicates no U-B value
Note on Num: Stars without the suffix r are the Bluest (Q < -0.7) and
    Brightest (V < 16) Stars in 30 Doradus.
Note on X, Y: coordinates are from the CCD finder charts in the reference
       Pixel sizes (in X and Y columns) are approximately 0.49 arcsec/pixel.
Note on V, B-V, U-B: magnitudes and colors in the Johnson UBV system.
--------------------------------------------------------------------------------

Byte-by-byte Description of file: tbl11-12.dat
--------------------------------------------------------------------------------
   Bytes Format  Units    Label    Explanations
--------------------------------------------------------------------------------
   1-  5  I5     ---      Num     *Running number
       6  A1     ---      rej      [r] An r indicates a star too faint or red
   7-  8  I2     h        RAh      Right ascension 2000
  10- 11  I2     min      RAm      Right ascension 2000
  13- 16  F4.1   s        RAs      Right ascension 2000
      19  A1     ---      DE-      Declination sign 2000
  20- 21  I2     deg      DEd      Declination 2000
  23- 24  I2     arcmin   DEm      Declination 2000
  26- 27  I2     arcsec   DEs      Declination 2000
  31- 35  F5.1   pix      X       *X position
  39- 43  F5.1   pix      Y       *Y position
  46- 50  F5.2   mag      V       *V magnitude
  53- 57  F5.2   mag      B-V     *B-V color
  60- 64  F5.2   mag      U-B     *U-B color
  67- 71  F5.2   mag      Q        Q = (U-B) - 0.72(B-V)
  75- 78  F4.2   mag      E(B-V)  *Color excess in B-V
  81- 85  F5.2   mag      Mv      *Absolute magnitude
  88- 91  F4.2   K        Teff    *Log effective temperature
  93- 98  F6.2   mag      Mbol    *Bolometric magnitude
 101-112  A12    ---      Sp      *Spectral type
 115-125  A11    ---      com     *Comments
--------------------------------------------------------------------------------
Note on Num: Stars without the suffix r are the Bluest (Q < -0.7) and
       Brightest (V < 16) Stars in 30 Doradus.
Note on X, Y: coordinates are from the CCD finder charts in the reference
       Pixel sizes (in X and Y columns) are approximately 0.49 arcsec/pixel.
Note on V, B-V, U-B: magnitudes and colors in the Johnson UBV system.
Note on E(B-V): is the color excess calculated from Q as discussed
       in Section 2 of Paper II.
Note on Mv: is the absolute V magnitude = V - Rv * E(B-V) - DM where
       Rv = 3.1, and the distance modulus DM = 18.5 mag.
Note on Teff: is the log10 of the effective temperature, and is
       calculated from Q or (B-V)0 as discussed in Section 3.1 of Paper II.
Note on Mbol: is the bolometric magnitude = Mv + BC, where BC is
       calculated from Teff as discussed in Section 3.1 of Paper II.
Note on Sp: Sp. Type is the spectral type and luminosity class as
        determined from spectroscopic observations.  One colon ":"
        indicates an uncertainty of one spectral subtype or luminosity
        class, and two colons "::" indicate a larger uncertainty.
Note on com:
  Comments are indicated by the following codes:
        a   --- strong / over-subtracted Balmer lines
        b   --- blend
        c   --- possible composite / spectrum contaminated by nearby star
        e   --- strong nebular emission in the Balmer lines
        f   --- foreground star
        j,J --- has been observed by the author and the spectrogram appears in
                 Figure 6 or 7 of Paper I.
        p   --- peculiar (details in text of Paper I)
        m,M --- has been observed by Melnick (1985, A&A, 153, 235)
        w,W --- has been observed by Walborn (1986, IAU Symp. 116, 185; 1992 -
                 unpublished classifications) or Walborn & Blades (1987, ApJ,
                 323, L65)
        z   --- ZAMS O star
        The uppercase letters "J", "M", "W", indicate the sources of the
                 spectral types listed in Column 14; two or all three letters
                 may be uppercase if they agree on the same classification.

References:
  Paper  I = Parker, J. Wm. 1993, AJ, 106, 560
  Paper II = Parker, J. Wm. & Garmany, C. D. 1993, AJ, 106, 1471

Historical Notes:
  * 17-May-1994: First archived
  * 15-Mar-1995: Corrected reference (PASP 104) and standardized this file (CDS)
================================================================================
(End)                 Nancy G. Roman [NASA/NSSDC/ADC]                17-May-1994

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