Limb-darkened angular diameters of stars with combined infrared and optical interferometry

We present the angular diameters, physical radii, and effective temperatures of five stars observed using both the Palomar Testbed Interferometer (PTI) and the Navy Prototype Optical Interferometer (NPOI). These preliminary results are part of a larger project focused on measuring the angular diameters of the 62 stars that have been observed with both instruments. We plan to achieve diameter accuracies of 0.5% or better through the combination of infrared- and visible-wavelength data from PTI and the NPOI, respectively. The difference in limb-darkening effects between the two wavelength regimes, together with other external parameters, will allow us to test the atmospheric models on which the limb-darkening corrections are based. High quality angular diameters for these stars will also lead to more accurate physical diameter measurements and effective temperature determinations.

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