THE ASTRONOMICAL JOURNAL    VOLUME 114, NUMBER 1, PAGE 326          JULY 1997

       THE MACHO PROJECT LMC VARIABLE STAR INVENTORY. V. CLASSIFICATION
                   AND ORBITS OF 611 ECLIPSING BINARY STARS

     C. ALCOCK[1,2], R. A. ALLSMAN[3], D. ALVES[1,2,10], T. S. AXELROD[4],
    A. C. BECKER[7], D. P. BENNETT[1,2], K. H. COOK[1,2], K. C. FREEMAN[4],
  K. GRIEST[2,5], C. H. S. LACY[12], M. J. LEHNER[2,5], S. L. MARSHALL[1,2],
  D. MINNITI[1,2], B. A. PETERSON[4], M. R. PRATT[2,6,7], P. J. QUINN[4,11],
   A. W. RODGERS[4], C. W. STUBBS[2,7], W. SUTHERLAND[8], AND D. L. WELCH[9]
                           (The MACHO Collaboration)

                                   ABSTRACT

     We report the characteristics of 611 eclipsing binary stars in the
     Large Magellanic Cloud found by using the MACHO Project photometry
     database. The sample is magnitude limited, and extends down the main
     sequence to about spectral type A0. Many evolved binaries are also
     included. Each eclipsing binary is classified according to the
     traditional scheme of the General Catalogue of Variable Stars (EA and
     EB), and also according to a new decimal classification scheme defined
     in this paper. The new scheme is sensitive to the two major sources of
     variance in eclipsing binary star light curves -- the sum of radii,
     and the surface-brightness ratio, and allow greater precision in
     characterizing the light curves. Examples of each type of light curve
     and their variations are given. Sixty-four of the eclipsing binaries
     have eccentric, rather than circular, orbits. The ephemeris and
     principal photometric characteristics of each eclipsing binary are
     listed in a table. Photometric orbits based on the Nelson-Davis-Etzel
     model have been fitted to all light curves. These data will be useful
     for planning future observations of these binaries. Plots of all data
     and fitted orbits and a table of the fitted orbital parameters are
     available on the AAS CD-ROM series, Vol. 9, 1997. These data are also
     available at the MACHO home page (http://wwwmacho.mcmaster.ca/).
     (c) 1997 American Astronomical Society.

[1]  Lawrence Livermore National Laboratory, Livermore, CA 94550;
     Electronic mail: alcock, alves, bennett, dminniti, kcook,
     stuart@igpp.llnl.gov
[2]  Center for Particle Astrophysics, University of California, Berkeley,
     CA 94720
[3]  Supercomputing Facility, Australian National University, Canberra,
     ACT 0200, Australia; Electronic mail: robyn@mso.anu.edu.au
[4]  Mt. Stromlo and Siding Spring Observatories, Australian National
     University, Weston, ACT 2611, Australia; Electronic mail: tsa, kcf,
     peterson, alex@mso.anu.edu.au
[5]  Department of Physics, University of California, San Diego, CA 92093;
     Electronic mail: kgriest, jguern, mlehner@ucsd.edu
[6]  Department of Physics, University of California, Santa Barbara, CA 93106
[7]  Departments of Astronomy and Physics, University of Washington, Seattle,
     WA 98195; Electronic mail: becker, mrp, stubbs@astro.washington.edu
[8]  Department of Physics, University of Oxford, Oxford OX1 3RH,
     U.K.; Electronic mail: w.sutherland@physics.ox.ac.uk
[9]  Department of Physics and Astronomy, McMaster University, Hamilton, ON
     L8S 4M1, Canada; Electronic mail: welch@physics.mcmaster.ca
[10] Department of Physics, University of California, Davis, CA 95616
[11] European Southern Observatory, Karl-Schwarzchild Str. 2, D-85748,
     Garching, Germany; Electronic mail: pjq@eso.org
[12] Department of Physics, University of Arkansas, Fayetteville,
     AR 72701; Electronic mail: clacy@comp.uark.edu