Peremennye Zvezdy

"Peremennye Zvezdy",
vol. 6, N 33 (2006)

USNO-B1.0 1381-0460341: a New Eclipsing Binary System Near V1500 Cyg

K. V. Sokolovsky#1, E. P. Pavlenko#2
#1 Sternberg Astronomical Institute and Astro Space Center of the Lebedev Physical Institute, Russian Academy of Sciences, Moscow, Russia;
#2 Crimean Astrophysical Observatory, Nauchny, Crimea, Ukraine.

Received:   28.11.2006;   accepted:   5.12.2006
(E-mail for contact:

Star Name: USNO-A2.0 1350-13606605, USNO-B1.0 1381-0460341
Coordinates (J2000): 21 11 12.45, +48 09 31.4
Variability type: EW;   Limits, System: 18.75 - 19.5 (V);    
Period: 0.2994 d;   Epoch(min): JD 2453562.3878

Several sessions of high-temporal-resolution BVRcIc photometry of V1500 Cyg (Nova Cygni 1975) field were carried out by one of the authors (E.P. Pavlenko) using the 2.6-m Shajn telescope of the Crimean Astrophysical Observatory equipped with an FLI IMG 1001E CCD camera (Litvinchova & Pavlenko 2006). We analysed images taken on May 9; July 8, 10; August 2 and 5, 2005 with the VAST software (Sokolovsky & Lebedev, 2005). As a result, we detected a previously unknown variable star USNO-B1.0 1381-0460341, in 4 arcminutes from V1500 Cyg, near the edge of our CCD images. It lies in the galactic plane, l = 89.78 deg., b = -0.02 deg.

The variable is an EW type eclipsing binary with the light elements: HJDmin = 2453562.3878 + 0.2994 x E. Its maximum brightness is 18.75m (V), the amplitude of variability is about 0.75 mag (V). The observed colors of USNO-B1.0 1381-0460341 are the following: B-V = 1.46+/-0.09; V-R = 0.82+/-0.05; R-I = 0.83+/-0.04. The values of interstellar reddening for V1500 Cyg are E(B-V) = 0.45, E(V-R) = 0.35 and E(R-I) = 0.37 (Kaluzny & Semeniuk, 1987). If these values are the same for the very close USNO-B1.0 1381-0460341, then the intrinsic colors could be B-V = 1.01, V-R = 0.47 and R-I = 0.46. There is no evidence for a color change during eclipses. BVRcIc magnitudes were calibrated using the standards C1, C2, and C3 near V1500 Cyg (Kaluzny & Semeniuk, 1987). Using the empiric period-luminosity-color relation for W UMa type stars (Rucinski, 2006), we can estimate the distance to our EW binary. The uncertainty of the above relation is +/-0.25 Mv, it affects the resulting distance stronger than the uncertainty in interstellar extinction. The distance to USNO-B1.0 1381-0460341 can be estimated as 2400+/-300 pc.

Acknowledgments: We would like to thank S. V. Antipin for helpful discussion and V.P. Goransky for providing software used for our light-curve analysis. This research has made use of Aladin interactive sky atlas, operated at CDS, Strasbourg, France.

Kaluzny, J., Semeniuk, I., 1987, Acta Astronomica, 37, 349
Litvinchova, A. A., Pavlenko, E. P., 2006, in Binary Stars as Critical Tools and Tests in Contemporary Astrophysics, IAU Symposium no. 240, held 22-25 August, 2006 in Prague, Czech Republic, S240-92
Rucinski, S.M., 2004, New Astronomy Reviews, 48, 703
Sokolovsky, K., Lebedev, A., 2005, in 12th Young Scientists' Conference on Astronomy and Space Physics, Kyiv, Ukraine, April 19-23, 2005, eds.: Simon, A.; Golovin, A., p.79 (VAST:

Light Curve
USNO-B1.0 1381-0460341: a New Eclipsing Binary System Near V1500 Cyg
Fig. 1. B, V, Rc and Ic phased light curves.
Finding Chart
USNO-B1.0 1381-0460341: a New Eclipsing Binary System Near V1500 Cyg
Fig. 2. The finding chart. V1500 Cyg is also shown.
Data Source
  1. usno-b1-1381-0460341_ccd.dat

Main Page | Search
Astronet | SAI | INASAN

Report problems