Constraining Parameters of HW Vir Binaries from the Pattern of Harmonics in their Light Curve Periodograms

HW Virginis systems are compact stellar binaries consisting of a hot subdwarf star and cool companion like a red dwarf or brown dwarf. Their light curves show a strong reflection effect in addition to primary and secondary eclipses. The exact light curve shape depends on several factors including the orbital period, inclination angle, mass ratio, radius ratio, and more. Here we use photometry of known HW Vir binaries observed by NASA’s Transiting Exoplanet Survey Satellite (TESS) to compute Lomb-Scargle periodograms and investigate whether the relative amplitudes of the harmonics in the periodograms can shed light on fundamental system parameters.