The first spectroscopic and photometric solutions of the eclipsing binary, V335 Ser

We present the first analyses of the radial velocity and BV light curves for the eclipsing binary system, V335 Ser. This double-lined eclipsing binary has an eccentricity of 0.14. BV photometric light curves and double-lined radial velocities were solved simultaneously using an improved version of the Wilson–Devinney computer program. The masses and radii of the component stars were obtained as M1 = 2.02 ± 0.01 M⊙, M2 = 1.84 ± 0.02 M⊙, R1 = 2.03 ± 0.02 R⊙ and R2 = 1.60 ± 0.01 R⊙. We estimated the semi-amplitudes of the radial velocity curves of the primary and secondary components as K1 = 106.31 ± 0.88 km s−1 and K2 = 116.94 ± 0.88 km s−1, respectively. As determined by absolute visual magnitude and corrections for interstellar extinction, the distance of the system from earth was found to be d = 219 ± 24 pc. The existence of apsidal motion is presented as means of eclipse time, and the apsidal motion rate was found to be ω˙obs=0.01302±0.02563degcycle-1. The corresponding apsidal motion period was found to be U = 261 ± 514 years. Using the absolute properties and apsidal motion parameters obtained from period analysis, we computed the observational and theoretical internal structure constants to be logk2,obs = −1.53 and logk2,theo = −2.44, respectively. We also present the evolutionary status of the component stars in an H-R diagram using solar metallicity and four helium content values. Both component stars are slightly evolved from the ZAMS.