V1073 Cygni: A New Light Curve and Analysis

Abstract

A new CCD light curve of the A-type W UMa star V1073 Cygni has been obtained, and the di †erential-corrections method of Wilson and Devinney was used to compute a new set of system parameters. The same analysis has been applied to the other photometric light curves in the literature, including the Hipparcos light curve. A new ephemeris is determined for the times of primary minimum. V1073 Cygni probably has initially formed as a detached system and evolved into contact.

Radial Velocity and Light Curves Analysis of the Contact Binary V1073 Cygni

“…Moreover, Wilson program (1998) was used in order to find simultaneous radial velocity and light curves solution of the system. Since the spectral type of V1073 Cyg was F1V, Ahn et al (1992), Sezer (1996) and Morris and Naftilan (2000) assigned a temperature 6700 (K) to the primary star as well, and this is the temperature used in the present analysis. Star 1 is about 206 K hotter than star 2.…”

“…According to Kopal (1959), relation r 1 + r 2 = 0.75 should be fulfilled for contact system; therefore, taking the mean values of r 1 and r 2 , we have r 1 + r 2 = 0.785. Therefore, according Ahn et al (1992) Sezer (1996 Morris and Naftilan (2000) to this criterion, V1073 Cyg is an overcontact one, with two stars overfilling their respective Roche lobes. In Table 4 we tabulate our results together with previous photometric solutions from other sources.…”

“…They found that the mass ratio and the temperature of the primary component of this system are q = 0.32 and T 1 = 6700 K, respectively. Sezer (1993) obtained photometric B and V light curves and used the WD program to find 3% overcontact and q = 0.436, assuming radiative behavior and T 1 = 8570 K. This light curves were reanalyzed in Sezer (1996) by assuming convective behavior and T 1 = 6700 K, finding 19%−22% overcontact, q = 0.306 and i = 69 • .4. The next observations of V1073 Cyg were made by Morris and Naftilan (2000).…”

“…Sezer (1993) obtained photometric B and V light curves and used the WD program to find 3% overcontact and q = 0.436, assuming radiative behavior and T 1 = 8570 K. This light curves were reanalyzed in Sezer (1996) by assuming convective behavior and T 1 = 6700 K, finding 19%−22% overcontact, q = 0.306 and i = 69 • .4. The next observations of V1073 Cyg were made by Morris and Naftilan (2000). They found the new set of system parameters by using WD program and also reported a new ephemeris for the times of primary minima.…”

“…were used as the comparison and check stars respectively. The phase of the observations was calculated by using the light elements given by Morris and Naftilan (2000).…”