Starspots in contact and semi-detached binary systems

Abstract

We investigated the statistical properties of both cool and hot starspots in eclipsing binary stars. The starspot and binary parameters for contact and semi-detached systems were collected from literature, which were determined on the basis of synthetic light-curve analysis. We examined associations between these parameters. As a result, the cool spots in W-type binaries show properties similar to those of sunspots and starspots generated by dynamos, which differs from those of the cool spots in A-type binaries. The properties of hot spots also differ between the W- and A-type samples. From the physical properties of A- and W-type binaries, we infer that mass transfer is a dominant process for forming the hot spots in A-type binaries; and both mass transfer and magnetic activity can contribute to the formation of the hot spots in W-type binaries. Our results also indicate that the hot-spot size in the A-type sample is correlated with the temperature of spotted stars, orbital period, mass ratio, and fill-out factor.

17 pages, 14 figures, accepted for publication in PASJ

References in corpus (43)

• Superflares on Solar-Type Stars Observed with Kepler II. Photometric Variability of Superflare-Generating Stars : A Signature of Stellar Rotation and Starspots
• Radial Velocity Studies of Close Binary Stars.I
• Radial Velocity Studies of Close Binary Stars.IV
• The short period end of the contact binary period distribution based on the All Sky Automated Survey (ASAS)
• Radial Velocity Studies of Close Binary Stars.II
• Radial Velocity Studies of Close Binary Stars.V
• Starspot activity and superflares on solar-type stars
• Radial Velocity Studies of Close Binary Stars.VIII
• Radial Velocity Studies of Close Binary Stars.VI
• Radial Velocity Studies of Close Binary Stars.III
• Radial Velocity Studies of Close Binary Stars. XI
• Radial Velocity Studies of Close Binary Stars. IX
• The short-period limit of contact binaries
• Masses and angular momenta of contact binary stars
• Radial Velocity Studies of Close Binary Stars. XII
• Detecting Stellar Spots by Gravitational Microlensing
• Radial Velocity Studies of Close Binary Stars.X
• Radial Velocity Studies of Close Binary Stars.XIII
• Radial Velocity Studies of Close Binary Stars. XV
• Radial Velocity Studies of Close Binary Stars. XIV
• Absolute properties of the binary system BB Pegasi
• High Fill-Out, Extreme Mass Ratio Overcontact Binary Systems. X. The new discovered binary XY Leonis Minoris
• Physical parameters of close binaries QX Andromedae, RW Comae Berenices, MR Delphini, and BD +07{\circ} 3142
• The Period Variation of and a Spot Model for the Eclipsing Binary AR Bootis
• Physical Parameters of Some Close Binaries: ET Boo, V1123 Tau, V1191 Cyg, V1073 Cyg and V357 Peg
• The Light and Period Variations of the Eclipsing Binary BX Draconis
• Photometric analysis of overcontact binaries AK Her, HI Dra, V1128 Tau and V2612 Oph
• Spurious 'active longitudes' in parametric models of heavily spotted eclipsing binaries
• Long-term Photometric Behavior of the Eclipsing Binary GW Cephei
• The Light and Period Variations of the Eclipsing Binary AA Ursae Majoris
• The First Comprehensive Photometric Study of the Algol-type System CL Aurigae
• Physical properties and evolutionary status of the W-subtype contact binary V502 Oph with a stellar companion
• The first photometric analysis of the W-subtype contact binary UCAC4 436-062932 with O'Connell effect
• Photometric observations from theoretical flip-flop models
• The Physical Nature and Orbital Behavior of the Eclipsing System DK Cygni
• Light curve analysis and orbital period change of the extreme mass-ratio overcontact binary AW CrB
• Photometric Properties of the Near-contact Binary GW Geminorum
• A Photometric Study of Four Recently Discovered Contact Binaries: 1SWASP J064501.21+342154.9, 1SWASP J155822.10-025604.8, 1SWASP J212808.86+151622.0 and UCAC4 436-062932
• Physical Nature and Timing Variations of the Eclipsing System V407 Pegasi
• Photometric study and period analysis of the contact binary XZ Leonis
• The period analysis of V418 Aql, SU Boo, RV CVn, CR Cas, GV Cyg, V432 Per, and BD+42 2782
• Photometric Investigation of the K-type Extreme-Shallow Contact Binary V1799 Orion
• Optical photometry and X-ray monitoring of the "Cool Algol" BD+05 706: Determination of the physical properties

Cited by in corpus (7)

• Statistics of 700 individually studied W UMa stars
• UVIT Open Cluster Study. II. Detection of extremely low mass white dwarfs and post-mass transfer binaries in M67
• A Bayesian Analysis of Physical Parameters for 783 Kepler (Near-)Contact Binaries: Extreme-Mass-Ratio Systems and a New Mass Ratio versus Period Lower Limit
• A survey for variable young stars with small telescopes: III -- Warm spots on the active star V1598Cyg
• Multiband analysis of the O'Connell effect in 14 eclipsing binaries
• Characteristics of Kepler Eclipsing Binaries Displaying a Significant O'Connell Effect
• Multi-wavelength photometric study of five contact binaries in the field of globular cluster M4