The N2K Consortium. IV. New Temperatures and Metallicities for More than 100,000 FGK Dwarfs

We have created a framework to facilitate the construction of specialized target lists for radial velocity surveys that are biased toward stars that (1) possess planets and (2) are easiest to observe with current detection techniques. We use a procedure that uniformly estimates fundamental stellar properties of Tycho 2 stars, with errors, using spline functions of broadband photometry and proper motion found in Hipparcos/Tycho 2 and 2MASS. We provide estimates of temperature and distance for 2.4 million Tycho 2 stars that lack trigonometric distances. For stars that appear to be FGK dwarfs according to estimated temperature and absolute magnitude, we also derive Fe/H and identify unresolved binary systems with mass ratios between 1.25 and 3. Our spline function models are trained on the unique Valenti the second tier is a low-resolution spectroscopy program headed by S.E. Robinson (astro-ph/0510150).