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II/66           A Catalogue of observations in H alpha    (Ducati, 1981)
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A Catalogue of observations in H alpha
   Ducati J.R.
  <Astron. Astroph. Suppl. 45, 119, (1981)>
  =1981A&AS...45..119D
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ADC_Keywords: Photometry, H-alpha ; Equivalent widths

Abstract:
    This catalogue contains 4095 published observations of the
    quantitative observations of H{alpha} for 2700 stars. These
    observations were collected from values published between
    1949 and 1980.

    The H{alpha} index was reduced to a common system described by
    Strauss & Ducati (1981A&AS...44..337S); the values of the
    original index can be retrieved with a linear transformation
    (cc = correlation coefficient):
    -----------------------------------------------------------------
        References   a       b      cc    lower  upper Spectral range
    -----------------------------------------------------------------
                 2  1.401  -1.604  0.972  1.050  1.170
                10  1.33   -2.4           0.000
                13  1.526   0.130  0.992  2.910  3.300
             14,36  0.343   0.814  0.949  1.400        O B A0
             14,36  0.269   0.969  0.972  1.470        A1 F G K M
    20,21,22,23,37  0.39   -0.55          1.200
             24,25  1.35   -1.48   0.922  1.020  1.170
    -----------------------------------------------------------------

File Summary:
--------------------------------------------------------------------------------
 FileName       Lrecl     Records        Explanations
--------------------------------------------------------------------------------
ReadMe             80           .        This file
obs.dat            66        4095        Published measurements
means.dat          20        2299        Homogeneous data
refs.dat           80          39        References in numerical order
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Byte-by-byte Description of file: obs.dat
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   Bytes Format Units   Label     Explanations
--------------------------------------------------------------------------------
   1-  6  I6    ---     HD        ? Star identification, usually HD
   7-  8  A2    ---     m_HD      HD suffix (/3,/0, A, B, etc.)
   9- 17  A9    ---     ID        Alternate designation
  18- 30  A13   ---     Sp        Spectral type from original reference
  31- 34  F4.2  mag     Vmag      ? Visual magnitude if provided
  35- 42  F8.3  ---     Ha        ? H alpha measurement
      43  A1    ---     u_Ha      Uncertainty code for H alpha
  46- 50  F5.3  ---     e_Ha      ? Mean error of H alpha measurement
  53- 54  A2    ---     x_Ha     * Method of measurement of Ha
  57- 60  F4.1  ---     o_Ha      ? Number of observations or weight
  61- 62  I2    ---     w_wt      ? Weight of weight
      63  I1    ---     rem      *[1,6]? Coded remarks
  65- 66  I2    ---     ref       [1/37] Reference number (file refs.dat)
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Note on x_Ha:
      M = photoelectric photometry, value given in magnitudes.
      W = data from microdensitometer tracings of stellar spectra
      R = spectrophotometric measurements, where R = H-alpha ratio
Note on rem:
      1 = Variable star
      2 = Possible variable star
      3 = Emission, mainly Be or Ae stars
      4 = Double or multiple system
      5 = Standard star
      6 = Mean value over several measurements
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Byte-by-byte Description of file: means.dat
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   Bytes Format Units   Label     Explanations
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   1-  9  A9    ---     ID        HD number or other name
  12- 16  F5.3  mag     Ha        H-alpha index on common system (see
                                    Strauss & Ducati, 1981A&AS...44..337S)
  19- 20  I2    ---     ref       [1/37] References to original data
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Byte-by-byte Description of file: refs.dat
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   Bytes Format Units   Label     Explanations
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   1-  2  I2    ---     ref       [1,37]+= Reference number
       3  A1    ---     Cont      [ab ] Continuation
   5- 80  A76   ---     source    Text of reference
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(End)   Nancy G. Roman [ADC/SSDOO], rev. F. Ochsenbein [CDS]         15-Aug-1995