Absolute properties of the neglected eclipsing B-type binary HD 194495

Abstract

We present the results of the high-resolution spectroscopic observations of the neglected binary system HD 194495 (B3 IV-V+B4 V). A combined analysis of three different photometric data set ( Tycho B _T and V _T photometry, H _p-band data of Hipparcos and V-band data of ASAS3 photometry) and radial velocities indicates that the system has an orbital period of 4.90494 ± 0.00005 days and an inclination of 69 ± 1 degrees. This solution yields masses and radii of M₁ = 7.57 ± 0.08 M_⊙ and R₁ = 5.82 ± 0.03 R_⊙ for the primary and M₂ = 5.46 ± 0.09 M_⊙ and R₂ = 3.14 ± 0.08 R_⊙ for the secondary. Based on the position of the two stars plotted on a theoretical H-R diagram, we find that the age of the system is ≳28 Myr, according to stellar evolutionary models. The spectroscopic and photometric results are in agreement with those obtained using theoretical predictions.