Frequency of Planets in Binaries

Abstract

The frequency of planets in binaries is an important issue in the field of extrasolar planet studies because of its relevance in the estimation of the global planet population of our galaxy and the clues it can give to our understanding of planet formation and evolution. Multiple stars have often been excluded from exoplanet searches, especially those performed using the radial velocity technique, due to the technical challenges posed by such targets. As a consequence and despite recent efforts, our knowledge of the frequency of planets in multiple stellar systems is still rather incomplete. On the other hand, the lack of knowledge about the binarity at the time of the compilation of the target samples means that our estimate of the planet frequency around single stars could be tainted by the presence of unknown binaries, especially if these objects have a different behavior in terms of planet occurrence. In a previous work we investigated the binarity of the objects included in the Uniform Detectability sample defined by Fisher and Valenti (2005), showing how more than 20% of their targets were, in fact, not single stars. Here, we present an update of this census, made possible mainly by the information now available thanks to the second Gaia Data Release. The new binary sample includes a total of 313 systems, of which 114 were added through this work. We were also able to significantly improve the estimates of masses and orbital parameters for most of the pairs in the original list, especially those at close separations. A few new systems with white dwarf companions were also identified. The results of the new analysis are in good agreement with the findings of our previous work, confirming the lack of difference in the overall planet frequency between binaries and single stars but suggesting a decrease in the planet frequency for very close pairs.}

25 pages, 5 figures

References in corpus (18)

• Detection Limits from the McDonald Observatory Planet Search Program
• Discovery of Two T Dwarf Companions with the Spitzer Space Telescope
• Properties of planets in binary systems. The role of binary separation
• Influence of Stellar Multiplicity On Planet Formation. II. Planets Are Less Common in Multiple-Star Systems with Separations Smaller than 1500 AU
• Most Sub-Arcsecond Companions of Kepler Exoplanet Candidate Host Stars are Gravitationally Bound
• The frequency of planets in multiple systems
• The Mass of the Candidate Exoplanet Companion to HD 33636 from Hubble Space Telescope Astrometry and High-Precision Radial Velocities
• A high binary fraction for the most massive close-in giant planets and brown dwarf desert members
• The CORALIE survey for southern extrasolar planets XVII. New and updated long period and massive planets
• The multiplicity of exoplanet host stars - Spectroscopic confirmation of the companions GJ3021B and HD27442B, one new planet host triple-star system, and global statistics
• Fourteen New Companions from the Keck & Lick Radial Velocity Survey Including Five Brown Dwarf Candidates
• Planets in Binaries: Formation and Dynamical Evolution
• The Visual Orbit of the 1.1-day Spectroscopic Binary σ^2 Coronae Borealis from Interferometry at the CHARA Array
• Detection of Planetary and Stellar Companions to Neighboring Stars via a Combination of Radial Velocity and Direct Imaging Techniques
• Spectroscopic binaries in the Solar Twin Planet Search program: from substellar-mass to M dwarf companions
• Constraining the orbit of the planet-hosting binary $\tau$ Boötis: Clues about planetary formation and migration
• Project 1640 Observations of the White Dwarf HD 114174 B
• MagAO Imaging of Long-period Objects (MILO). II. A Puzzling White Dwarf around the Sun-like Star HD 11112

Cited by in corpus (8)

• Gap, shadows, spirals, streamers: SPHERE observations of binary-disk interactions in GG Tau A
• Multiple Stellar Evolution: a population synthesis algorithm to model the stellar, binary, and dynamical evolution of multiple-star systems
• On dust evolution in planet-forming discs in binary systems. I -- Theoretical and numerical modelling: radial drift is faster in binary discs
• Exoplanets with ELT-METIS I: Estimating the direct imaging exoplanet yield around stars within 6.5 parsecs
• CoBiToM Project -- I. Contact Binaries Towards Merging
• Long live the disk: lifetimes of protoplanetary disks in hierarchical triple star systems and a possible explanation for HD 98800 B
• A photospheric and chromospheric activity analysis of the quiescent retrograde-planet host $\nu$ Octantis A
• A white dwarf bound to the transiting planetary system WASP-98