INFLUENCE OF STELLAR MULTIPLICITY ON PLANET FORMATION. III. ADAPTIVE OPTICS IMAGING OFKEPLERSTARS WITH GAS GIANT PLANETS

Abstract

As hundreds of gas giant planets have been discovered, we study how these planets form and evolve in different stellar environments, specifically in multiple stellar systems. In such systems, stellar companions may have a profound influence on gas giant planet formation and evolution via several dynamical effects such as truncation and perturbation. We select 84 Kepler Objects of Interest (KOIs) with gas giant planet candidates. We obtain highangular resolution images using telescopes with adaptive optics (AO) systems. Together with the AO data, we use archival radial velocity data and dynamical analysis to constrain the presence of stellar companions. We detect 59 stellar companions around 40 KOIs for which we develop methods of testing their physical association. These methods are based on color information and galactic stellar population statistics. We find evidence of suppressive planet formation within 20 AU by comparing stellar multiplicity. The stellar multiplicity rate for planet host stars is 0 +5 −0 % within 20 AU. In comparison, the stellar multiplicity rate is 18%±2% for the control sample, i.e., field stars in the solar neighborhood. The stellar multiplicity rate for planet host stars is 34%±8% for separations between 20 and 200 AU, which is higher than the control sample at 12%±2%. Beyond 200 AU, stellar multiplicity rates are comparable between planet host stars and the control sample. We discuss the implications of the results to gas giant planet formation and evolution.

FRIENDS OF HOT JUPITERS. IV. STELLAR COMPANIONS BEYOND 50 au MIGHT FACILITATE GIANT PLANET FORMATION, BUT MOST ARE UNLIKELY TO CAUSE KOZAI–LIDOV MIGRATION

“…However, surveys of star-forming regions indicate that binaries with separations less than 50 au have significantly shorter disk lifetimes, while binaries with larger separations appear to have disk lifetimes comparable to those of single stars (e.g., Kraus et al 2012). In addition, Kraus et al (2016) surveyed 382 Kepler planet host stars and found that there is a s 4.6 deficit in stars with binaries closer than 50 au compared to field stars, suggesting that these close binaries negatively influence planet formation (see also Wang et al 2015). We therefore change our approach in this analysis to consider the multiplicity rate for companions interior and exterior to 50 au separately.…”

“…More recently, there have been four large direct imaging surveys for companions to transiting gas giant planet hosts (Wang et al 2015;Evans et al 2016). applied stellar density arguments to estimate that 12 out of their 49 targets have bound companions, while report candidate companions around 33 out of 74 systems.…”

“…Although these studies do not confirm common proper motion or report a survey sensitivity corrected companion rate, their raw companion fractions are consistent with ours. Wang et al (2015) and Evans et al (2016) did check for common proper motion and correct for survey sensitivity. Wang et al (2015) report a stellar multiplicity rate for Kepler hot Jupiter hosts to be  51% 13% and Evans et al (2016) found a companion rate of -+ 38 % 13 17 .…”

“…Wang et al (2015) and Evans et al (2016) did check for common proper motion and correct for survey sensitivity. Wang et al (2015) report a stellar multiplicity rate for Kepler hot Jupiter hosts to be  51% 13% and Evans et al (2016) found a companion rate of -+ 38 % 13 17 . Both of these results are in good agreement with our previously published value.…”

Probability of the Physical Association of 104 Blended Companions to Kepler Objects of Interest Using Visible and Near-Infrared Adaptive Optics Photometry

“…Bechter et al 2014;Wang et al 2014Wang et al , 2015. Photometric values for the Keplerband were computed by the method described in Brown et al (2011) using an arithmetic combination of gri colors.…”