Eclipsing binary UU Cas: Radial-velocity curves

Abstract

This paper reports the results of spectroscopic observations of UUCas obtained with the highresolution (R = 15 000) fiber-fed echelle spectrometer of the 1.2-m telescope of Kourovka Astronomical Observatory of Ural Federal University. The radial velocities of the secondary, more massive and fainter component are measured for the first time. The component mass ratio is found to be q = M₁/M₂ = 0.54. The component masses, M₁ = 9.5M_⊙ and M₂ = 17.7M_⊙, and the radius of the or bit, A = 52.7R_⊙, are computed for the published orbital inclination of i ~ 69°. Evidence is presented for a disk surrounding the more massive component and a common expanding envelope.