A Pan-STARRS1 study of the relationship between wide binarity and planet occurrence in the Kepler field

TL;DR

This study investigates whether wide binary star systems influence the occurrence of exoplanets around FGK stars in the Kepler field, finding no significant effect for binaries separated by more than 3000 AU.

Contribution

It introduces a probabilistic method to identify wide binaries in the Kepler field using Pan-STARRS1 data and assesses their impact on planet occurrence.

Findings

Wide binaries above 6 arcseconds separation do not affect planet occurrence.

No difference in planet hosting likelihood between binary and single stars.

Developed stellar SED templates and magnitude conversions for Pan-STARRS1 and Kepler.

Abstract

The NASA Kepler mission has revolutionised time-domain astronomy and has massively expanded the number of known extrasolar planets. However, the effect of wide multiplicity on exoplanet occurrence has not been tested with this dataset. We present a sample of 401 wide multiple systems containing at least one Kepler target star. Our method uses Pan-STARRS1 and archival data to produce an accurate proper motion catalogue of the Kepler field. Combined with Pan-STARRS1 SED fits and archival proper motions for bright stars, we use a newly developed probabilistic algorithm to identify likely wide binary pairs which are not chance associations. As by-products of this we present stellar SED templates in the Pan-STARRS1 photometric system and conversions from this system to Kepler magnitudes. We find that Kepler target stars in our binary sample with separations above 6 arcseconds are no more or less likely to be identified as confirmed or candidate planet hosts than a weighted comparison sample of Kepler targets of similar brightness and spectral type. Therefore we find no evidence that binaries with projected separations greater than 3,000AU affect the occurrence rate of planets with P<300days around FGK stars.