NAVY PROTOTYPE OPTICAL INTERFEROMETER OBSERVATIONS OF THE DOUBLE STARS MIZAR A AND MATAR

We present a detailed analysis of two spectroscopic binaries based on new observations obtained with the Navy Prototype Optical Interferomet er (NPOI). While the data calibration needs refinement, first results show the impressive potential of NPOI, both in terms of speed and prec ision, for imaging and modeling the orbits of spectroscopic binaries. We determine the orbital parameters of Mizar A (zeta(1) Ursae Majoris) and Matar (eta Pegasi), and derive masses and luminosities using publ ished radial velocities and Hipparcos trigonometric parallaxes. The re sults on Mizar A are compared to earlier work done with the Mark III i nterferometer, while data from this instrument were combined with NPOI data in the Matar analysis.