Marc H. Pinsonneault, Deokkeun An, Joanna Molenda-Żakowicz, William J. Chaplin, Travis S. Metcalfe, Hans Bruntt
We present a catalog of revised effective temperatures for stars observed in
long-cadence mode in the Kepler Input Catalog (KIC). We use SDSS griz filters
tied to the fundamental temperature scale. Polynomials for griz
color-temperature relations are presented, along with correction terms for
surface gravity effects, metallicity, and statistical corrections for binary
companions or blending. We compare our temperature scale to the published
infrared flux method (IRFM) scale for VJKs in both open clusters and the Kepler
fields. We find good agreement overall, with some deviations between (J -
Ks)-based temperatures from the IRFM and both SDSS filter and other diagnostic
IRFM color-temperature relationships. For field dwarfs we find a mean shift
towards hotter temperatures relative to the KIC, of order 215 K, in the regime
where the IRFM scale is well-defined (4000 K to 6500 K). This change is of
comparable magnitude in both color systems and in spectroscopy for stars with
Teff below 6000 K. Systematic differences between temperature estimators appear
for hotter stars, and we define corrections to put the SDSS temperatures on the
IRFM scale for them. When the theoretical dependence on gravity is accounted
for we find a similar temperature scale offset between the fundamental and KIC
scales for giants. We demonstrate that statistical corrections to color-based
temperatures from binaries are significant. Typical errors, mostly from
uncertainties in extinction, are of order 100 K. Implications for other
applications of the KIC are discussed.
View original:
http://arxiv.org/abs/1110.4456
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