Revised Stellar Properties of Kepler Targets for the Q1-17 (DR25) Transit Detection Run

TL;DR

This paper provides an updated catalog of stellar properties for nearly 200,000 Kepler targets, improving the accuracy of exoplanet characterization by refining stellar parameters using enhanced methods and additional data.

Contribution

The study introduces a revised stellar property catalog for Kepler targets with significant methodological improvements and new data, enhancing the accuracy of stellar and exoplanet analyses.

Findings

Uncertainties reduced to ~27% in radius and ~17% in mass.

Increased number of evolved solar-type stars by 43.5%.

Improved stellar parameters aid in better exoplanet characterization.

Abstract

The determination of exoplanet properties and occurrence rates using Kepler data critically depends on our knowledge of the fundamental properties (such as temperature, radius and mass) of the observed stars. We present revised stellar properties for 197,096 Kepler targets observed between Quarters 1-17 (Q1-17), which were used for the final transiting planet search run by the Kepler Mission (Data Release 25, DR25). Similar to the Q1--16 catalog by Huber et al. the classifications are based on conditioning published atmospheric parameters on a grid of Dartmouth isochrones, with significant improvements in the adopted methodology and over 29,000 new sources for temperatures, surface gravities or metallicities. In addition to fundamental stellar properties the new catalog also includes distances and extinctions, and we provide posterior samples for each stellar parameter of each star. Typical uncertainties are ~27% in radius, ~17% in mass, and ~51% in density, which is somewhat smaller than previous catalogs due to the larger number of improved logg constraints and the inclusion of isochrone weighting when deriving stellar posterior distributions. On average, the catalog includes a significantly larger number of evolved solar-type stars, with an increase of 43.5% in the number of subgiants. We discuss the overall changes of radii and masses of Kepler targets as a function of spectral type, with particular focus on exoplanet host stars.