=======================================================================
               The OGLE Collection of Variable Stars
        Over 75 000 Eclipsing Binaries in the Magellanic Clouds

  M. Glowacki, I. Soszynski, A. Udalski, M. K. Szymanski, J. Skowron,
  D. M. Skowron, P. Mroz, P. Pietrukowicz, R. Poleski, S. Kozlowski,
  P. Iwanek, M. Wrona, K. Ulaczyk, K. Rybicki, M. Gromadzki, M. Mroz,
                         and M. Urbanowicz

=======================================================================
mglowacki@astrouw.edu.pl
soszynsk@astrouw.edu.pl

This directory contains the OGLE catalog of eclipsing and ellipsoidal
binary systems in the Small Magellanic Cloud.

The directory structure is as follows:

README            - this file

ident.dat         - identification of stars

ecl.dat           - parameters of eclipsing binary systems
ell.dat           - parameters of ellipsoidal binary systems

phot/I/           - I-band OGLE-IV photometry of individual objects
phot/V/           - V-band OGLE-IV photometry of individual objects
phot.tar.gz       - gzipped phot/ directory

fcharts/          - finding charts of individual objects

remarks.txt       - remarks on selected objects

paper.pdf         - PDF version of the paper Glowacki et al. (2025),
                    Acta Astron. .., ..., (arXiv:............) describing
                    the collection.


Format of the file ident.dat:
--------------------------------------------------------------------------
 Bytes  Format Units   Description
--------------------------------------------------------------------------
  1- 18  A18   ---     Star's ID
 21- 23  A3    ---     Subtype (C - contact, NC - non-contact, CV - cata-
                       clysmic variable, ELL - ellipsoidal variable) 
 25- 26  I2    h       Right ascension, equinox J2000.0 (hours)
 28- 29  I2    m       Right ascension, equinox J2000.0 (minutes)
 31- 35  F5.2  s       Right ascension, equinox J2000.0 (seconds)
     37  A1    ---     Declination, equinox J2000.0 (sign)
 38- 39  I2    deg     Declination, equinox J2000.0 (degrees)
 41- 42  I2    arcmin  Declination, equinox J2000.0 (arc minutes)
 44- 47  F4.1  arcsec  Declination, equinox J2000.0 (arc seconds)
 50- 65  A16   ---     OGLE-IV ID
 67- 81  A15   ---     OGLE-III ID
 83- 97  A15   ---     OGLE-II ID
 99-     A     ---     Other designation
--------------------------------------------------------------------------

Format of the files ecl.dat and ell.dat:
--------------------------------------------------------------------------
 Bytes  Format Units   Description
--------------------------------------------------------------------------
  1- 18  A18   ---     Star's ID
 21- 26  F6.3  mag     I-band magnitude at the maximum light
 28- 33  F6.3  mag     V-band magnitude at the maximum light
 35- 46  F12.7 days    Orbital period
 49- 60  F12.4 days    Epoch of of the primary eclipse (HJD)
 63- 67  F5.3  mag     Depth of the primary eclipse
 69- 73  F5.3  mag     Depth of the secondary eclipse
--------------------------------------------------------------------------

Format of the files with photometry (phot/I/OGLE-SMC-ECL-NNNNN.dat,
phot/V/OGLE-SMC-ECL-NNNNN.dat)
--------------------------------------------------------------------------
 Bytes  Format Units   Description
--------------------------------------------------------------------------
  1- 13  F13.5 days    Heliocentric Julian Day
 15- 20  F6.3  mag     Magnitude
 22- 26  F5.3  mag     Uncertainty of magnitude
--------------------------------------------------------------------------

Finding charts are gzipped Postscript images. The names of the files are in
the form: ID.ps.gz. The finding charts are 60"x60" subframes of the I-band
reference frames centered on the star. White cross marks the star. North is
up and East to the left.


Any presentation of the scientific analysis or usage of the data from the
catalog of classical Cepheids in the Galactic bulge should include the
appropriate reference(s) to OGLE paper(s).