c © 2009. The American Astronomical Society. All rights reserved. Printed in the U.S.A. ANGULAR DIAMETERS OF THE HYADES GIANTS MEASURED WITH THE CHARA ARRAY

We present angular diameters of the Hyades giants, γ, δ1, , and θ1 Tau from interferometric measurements with the CHARA Array. Our errors in the limb-darkened angular diameters for these stars are all less than 2%, and in combination with additional observable quantities, we determine the effective temperatures, linear radii, and absolute luminosities for each of these stars. Additionally, stellar masses are inferred from model isochrones to determine the surface gravities. These data show that a new calibration of effective temperatures with errors well under 100 K is now possible from interferometric angular diameters of stars