We perform a search for wide binaries in the Kepler field with the prospect
of providing new constraints for gyrochronology. First, we construct our base
catalog by compiling astrometry for the stars observed by Kepler, and
supplement it with parallaxes, radial velocities (RVs), and metallicities. We
then mine our base catalog for wide binary candidates by matching the stars'
proper motions, as well as parallaxes, RVs, and metallicities, if available. We
mitigate the presence of chance alignments among our candidates by performing a
comprehensive data-based contamination analysis in the proper motion versus
angular separation phase space. Our final sample contains 55 binary candidates.
A crossmatch of our pairs with the Second Data Release (DR2) from Gaia
validates our candidates and confirms the reliability of our search method,
particularly for ϖ≳2 mas. Due to the implicit Kepler selection
function and image scale per pixel, our binary search is incomplete for angular
separations of less than 20 arcsec. We crossmatch our candidates with rotation
period and asteroseismic ages catalogs, and find that our binary candidates do
not follow a simple period-color relation, in agreement with previous studies.
Two pairs have an age estimate for one component star and rotation period for
its companion, positioning them as potentially new gyrochronology constraints
at old ages. This is the first study that uses RVs and metallicities as
criteria, rather than as a confirmation, in a binary search.Comment: 32 pages, 17 figures; accepted for publication in MNRA
