Astronomical Data Center

ADCADC/CDS Standard Document for Catalog:
/journal_tables/AJ/101/1763/

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

1. Use the ADC Data Viewer Suite to visualize the data. [preview
2. Get the data files via anonymous FTP. (See Note.) [ftp


II/162    CCD search in Crux and Centaurus (Caldwell+, 1991)
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A scanner CCD search for Cepheids and other variables in Crux and Centaurus.
       Caldwell J.A.R., Keane M.J., Schechter P.L.
      <Astron. J., 101, 1763 (1991)>
      =1991AJ....101.1763C   (SIMBAD/NED Reference)
================================================================================
ADC_Keywords: Stars, variable; Photometry 

Abstract:
   This catalog contains the results of a photometric survey for variable stars 
   in a 9.4 square degree region along the galactic plane in Crux and Centaurus.
   A total of 300 308 stars were observed at seven epochs over 42 days;
   224 524 of these stars were detected at multiple epochs and were tested
   for possible variations in brightness that exceed observational error.
   2422 stars are identified as variable at a formal confidence level of 99%;
   270 of the new variables brighter than I=14.0 are classified as long
   period variables. A list of 242 likely short period variables with RMS
   amplitudes >=0.060mag is given. From this list, 37 Cepheid candidates
   were selected after inspection of their light curves.

File Summary:
--------------------------------------------------------------------------------
 FileName     Lrecl  Records    Explanations
--------------------------------------------------------------------------------
ReadMe           80        .    This file
data1.dat        79    19124    The complete list of probable variables
data2.dat        79   225052    Observations with RA = 11 39 40 to 12 15 41 and
                                declination = -63 05 12 to -62 46 46 (1950) 
data3.dat        79   207787    Observations with RA = 11 39 40 to 12 15 12 and
                                declination = -62 46 47 to -62 27 26 (1950) 
data4.dat        79   254005    Observations with RA = 11 39 40 to 12 14 44 and
                                declination = -62 27 27 to -62 03 11 (1950)  
data5.dat        79   175070    Observations with RA = 11 39 40 to 12 14 16 and
                                declination = -62 03 12 to -61 47 46 (1950)  
data6.dat        79   187418    Observations with RA = 11 39 39 to 12 13 48 and
                                declination = -61 47 47 to -61 24 46 (1950)  
data7.dat        79   224071    Observations with RA = 13 10 14 to 13 46 17 and
                                declination = -63 06 09 to -62 54 03 (1950)  
data8.dat        79   182283    Observations with RA = 13 10 15 to 13 45 52 and
                                declination = -62 53 19 to -62 36 32 (1950)  
data9.dat        79    80086    Observations with RA = 13 10 15 to 13 45 28 and
                                declination = -62 35 49 to -62 23 27 (1950)  
table4.dat       69      242    High amplitude, short-period variables found
                                in this survey
table5.dat       61      270    Long-period variables found in this survey
table6.dat       64      127    Variable stars identified with IRAS 12 {mu}m
                                sources
table7.dat       54       18   *The ABCS carbon stars detected as variables
                                in this survey
--------------------------------------------------------------------------------
Note on table7: ABCS: Aaronsom M. et al., 1989, ApJS 70, 637

Byte-by-byte Description of file: data*.dat
--------------------------------------------------------------------------------
   Bytes     Format      Units    Label     Explanations
--------------------------------------------------------------------------------
   1-  4      I4         ---      image     Image number
   5-  8      I4         ---      no        Number of object within the image
  10- 11      I2         h        RAh       Right Ascension, hours (1950)
  13- 14      I2         min      RAm       Right Ascension, minutes (1950)
  16- 20      F5.2       s        RAs       Right Ascension, seconds (1950)
      22      A1         ---      DE-       Declination sign
  23- 24      I2         deg      DEd       Declination, degrees (1950)
  26- 27      I2         arcmin   DEm       Declination, minutes (1950)
  29- 32      F4.1       arcsec   DEs       Declination, seconds (1950)
  34- 39      F6.3       mag      I         Cousins I magnitude
  41- 45      F5.3       mag      e_I      *Formal uncertainty in I
  47- 55      F9.4       d        MJD       Mean Julian Day
  57- 62      F6.2       pix      x        *X position within the image
  64- 70      F7.2       pix      y        *Y position within the image
      72      I1         ---      class    *Object classification
      74      I1         ---      ID       *Catalog from which it is drawn
  75- 79      I5         ---      num_ID    Number in source catalog
--------------------------------------------------------------------------------
Note on e_I:
   Stars with centroids within 12 pixels of the beginning of the image
   (which, unfortunately, includes the first stars on the variable star
   list) may have suffered from a software bug in the data acquisition and
   may have errors bigger than the formal errors.

Note on x and y:
   The pixels are not square. They are 0.45" in the x direction and either
   3.7" or 1.85" in the y direction. The latter are less frequent and go
   somewhat fainter than the lower resolution observations.

Note on class:
   1 = single star
   2 = galaxy
   3 = one component of a multiple star
   4 = an object for which the classification is uncertain
   5 = too few pixels to determine classification or for which a position
       was derived beyond the boundaries of the image or fit subraster
   6 = should not be in the catalog
   7 = too faint to attempt classification
   8 = could not be modeled (too bright or cosmic ray) and has been excised

Note on ID:
   This is a sequence number assigned for internal use. The decoding is
   unavailable.

Byte-by-byte Description of file: table4.dat, table5.dat 
--------------------------------------------------------------------------------
   Bytes Format  Units   Label    Explanations
--------------------------------------------------------------------------------
   1- 10  A10    ---     Name     Variable name
      11  A1     ---     m_Name   Multiplicity index on Name
  13- 14  I2     h       RAh      Right ascension 1950
  16- 17  I2     min     RAm      Right ascension 1950
  19- 23  F5.2   s       RAs      Right ascension 1950
      25  A1     ---     DE-      Declination sign
  26- 27  I2     deg     DEd      Declination 1950
  29- 30  I2     arcmin  Dem      Declination 1950
  32- 35  F4.1   arcsec  DEs      Declination 1950
  37- 41  F5.2   mag     Imag     I magnitude
  43- 47  F5.3   mag     e_Imag   []? rms uncertainty on Imag
  49- 68  A20    ---     Notes    Notes (1)
--------------------------------------------------------------------------------
Note (1):  1. 1st rank Cepheid candidate.
           2. 2nd rank Cepheid candidate.
           3. Possible eclipse.
           4. Possible LPV.
           5. Additional photometry obtained 1990 Feb-Apr.
           6. Variable is also identified as an IRAS 12{mu} source, see Table 6
           7. Variable is also identified as a carbon star, see Table 7
    Note: the remarks in table 5 are in bytes 49-61. 
--------------------------------------------------------------------------------

Byte-by-byte Description of file: table6.dat 
--------------------------------------------------------------------------------
   Bytes Format  Units   Label    Explanations
--------------------------------------------------------------------------------
   1- 10  A10    ---     Name     Variable name
  13- 14  I2     h       RAh      Right ascension 1950
  16- 17  I2     min     RAm      Right ascension 1950
  19- 23  F5.2   s       RAs      Right ascension 1950
      25  A1     ---     DE-      Declination sign
  26- 27  I2     deg     DEd      Declination 1950
  29- 30  I2     arcmin  Dem      Declination 1950
  32- 35  F4.1   arcsec  DEs      Declination 1950
  37- 41  F5.2   mag     Imag     I magnitude
  43- 52  A10    ---     IRAS     IRAS source
  54- 64  A11    ---     Notes    Notes (1)
--------------------------------------------------------------------------------
Note (1):  1. Variable was classified as LPV and is also listed in Table 5.
           2. Variable was classified as short-period variable and is also
               listed in Table 4. Likely a long period variable observed near
               minimum or maximum light.
           3. Object is also identified as a carbon star, see Table 7
--------------------------------------------------------------------------------

Byte-by-byte Description of file: table7.dat
--------------------------------------------------------------------------------
   Bytes Format  Units   Label    Explanations
--------------------------------------------------------------------------------
   1-  5  A5     ---     ABCS     Aaronsom C stars (1)
   7- 16  A10    ---     Name     Variable star name
  18- 19  I2     h       RAh      Right ascension 1950
  21- 22  I2     min     RAm      Right ascension 1950
  24- 28  F5.2   s       RAs      Right ascension 1950
      30  A1     ---     DE-      Declination sign
  31- 32  I2     deg     DEd      Declination 1950
  34- 35  I2     arcmin  DEm      Declination 1950
  37- 40  F4.1   arcsec  DEs      Declination 1950
  42- 54  A13    ---     Notes    Notes (2)
--------------------------------------------------------------------------------
Note (1): Aaronsom M. et al., 1989, ApJS 70, 637
Note (2): 1. Classified as a LPV, see Table 5.
          2. Also identified with an IRAS 12{mu} source, see Table 6.
--------------------------------------------------------------------------------

Historical note: The tables were keypunched at CDS; the data files were
   provided by Dr. P. L. Schechter.  The portion of this document which 
   refers to the tables and the Description were prepared by Simona Mei and
   Patricia Bauer of the CDS in December 1994.
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(End)    Nancy Grace Roman       [SSDOO/ADC]            Apr-30-96               

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