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Paper: Binary Stars and their Light Curves
Volume: 349, Astrophysics of Variable Stars
Page: 71
Authors: Wilson, R.E.
Abstract: This guide to persons newly entering the eclipsing binary field begins by comparing eclipsing binary modeling and analysis with the corresponding problems for visual and spectroscopic binaries, including issues of data quantity, reliability, and astrophysical information content. Emphasis is on the value of intuition acquired by visualization, by numerical-graphical experiments, and by examination of graphs during the progress of a solution. An important part of a solution is in judgments as to what can realistically be found, so as not to attempt the impossible yet optimally extract the resident information. Intuition is needed to get close and to recognize false solutions (avoid possible local minima). Effects on light curves of ellipsoidal variation, reflection, and surface irregularities are discussed. Parameter combinations to be found from light curves alone, velocity curves alone, and light and velocity curves together are tabulated. Schemes to deal with uniqueness and convergence problems include the Levenberg-Marquardt algorithm, the Method of Multiple Subsets, and Vector Length Reduction. Orbital ephemerides are most often found by eclipse timings, although a relatively new way is by inclusion of ephemeris parameters in solutions of mixed whole light and velocity curves. Apsidal motion may also be found from whole curve solutions. Close binary morphology is reviewed, including its origins, conceptual basis, and relation to binary system evolution. The connection between morphology and solutions can be introduced by solution constraints that reduce parameter lists. Photometric mass ratio foundations are discussed, with comparison of the semi-detached and overcontact cases and of the complete and partial eclipse cases. A few common misconceptions are mentioned and some new directions are briefly indicated. The guide concludes with solution strategies and weighting, including things to avoid in both of those areas.
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