Close Binary Star Observables: Modeling Innovations 2003-06

Innovation in synthesis and analysis of time-wise binary star observables (light curves, radial velocity curves, etc.) continued above its usual brisk pace over the triennium (mid-2003 to mid 2006), stimulated by planned space missions, by large surveys such as ASAS, Gaia, and the gravitational lens surveys, and by instrumental advances. Particularly notable are syntheses of observables beyond light and velocity curves such as line spectra and line profiles; surface and circum-stellar phenomena such as magnetic spots, extended atmospheres, and dynamic flows; binaries as distance indicators; and automated schemes to process enormous databases. Other work addressed advantages of working with light curves that are effectively or actually in absolute units; detection and analysis of multiple systems; accuracy of photometric mass ratios; effects of interstellar and Earth-atmosphere extinction on light curves, ephemerides from mixed whole light and velocity curves, user-friendly interface capability; and convergence and uniqueness of light curve solutions. Synthesized star and disk spectra are probing exotic systems such as cataclysmic variables, polars, and X-ray binaries. They also allow objective measurement of rotation via line profiles and meaningful analysis of systems with shallow or absent eclipses. Work on neural networks and on large archives promises to supply the starting parameter estimates needed by automated light curve solution programs that are intended mainly for surveys but may also be useful for individually observed objects. Distance estimation now can be self-contained and impersonal, with efficient through-put and standard errors, and can be applied fully as well to semi-detached and over-contact as to detached binaries.