The sdB+M Eclipsing System HW Virginis and its Circumbinary Planets

Abstract

For the very short-period sdB eclipsing binary HW Vir, we present new CCD photometry made from 2000 through 2008. In order to obtain consistency of the binary parameters, our new light curves were analyzed simultaneously with previously published radial-velocity data. The secondary star parameters of $M_2$=0.14 M${}_{\odot }$, $R_2$=0.18 R${}_{\odot }$, and $T_2$=3,084 K are consistent with those of an M6-7 main sequence star. More than 250 times of minimum light, including our 41 timings and spanning more than 24 yrs, were used for a period study. From a detailed analysis of the $O$--$C$ diagram, it emerged that the orbital period of HW Vir has varied as a combination of a downward-opening parabola and two sinusoidal variations, with cycle lengths of $P_3$=15.8 yr and $P_4$=9.1 yr and semi-amplitudes of $K_3$=77 s and $K_4$=23 s, respectively. The continuous period decrease with a rate of $-8.28\times 10^{-9}$ d yr${}^{-1}$ may be produced by angular momentum loss due to magnetic stellar wind braking but not by gravitational radiation. Of the possible causes of the cyclical components of the period change, apsidal motion and magnetic period modulation can be ruled out. The most reasonable explanation of both cyclical variations is a pair of light-travel-time effects driven by the presence of two substellar companions with projected masses of $M_3\sin i_3$=19.2 M${}_{\mathrm{Jup}}$ and $M_4\sin i_4$=8.5 M${}_{\mathrm{Jup}}$. The two objects are the first circumbinary planets known to have been formed in a protoplanetary disk as well the first ones discovered by using the eclipse-timing method. The detection implies that planets could be common around binary stars just as are planets around single stars and demonstrates that planetary systems formed in a circumbinary disk can survive over long time scales.

26 pages, including 5 figures and 8 tables, accepted for publication in AJ

References in corpus (17)

• Long-Term Stability of Planets in Binary Systems
• The Theory of Brown Dwarfs and Extrasolar Giant Planets
• The Origin of Subdwarf B Star (I): the Formation Channels
• The origin of sdB stars (II)
• Origins of Eccentric Extrasolar Planets: Testing the Planet-Planet Scattering Model
• How Dry is the Brown Dwarf Desert?: Quantifying the Relative Number of Planets, Brown Dwarfs and Stellar Companions around Nearby Sun-like Stars
• Debris disks in main sequence binary systems
• Discovery of a Jupiter/Saturn Analog with Gravitational Microlensing
• A Young White Dwarf Companion to Pulsar 1620-26: Evidence for Early Planet Formation
• Constraints on resonant-trapping for two planets embedded in a protoplanetary disc
• Evolution of Planetary Systems in Resonance
• On the formation and migration of giant planets in circumbinary discs
• Terrestrial Planet Formation Surrounding Close Binary Stars
• 2MASS J05162881+2607387: A New Low-Mass Double-Lined Eclipsing Binary
• Extrasolar planet detection by binary stellar eclipse timing: evidence for a third body around CM Draconis
• An evolutionary study of the pulsating subdwarf B eclipsing binary PG1336-018 (NY Vir)
• An Algorithm For Photometric Identification Of Transiting Circumbinary Planets

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