VW Cygni: new photometric and polarimetric observations

An analysis of linear polarization for an eclipsing variable star VW Cyg is performed. The dependence of polarization values on the phase of orbital period is derived. The wavelength dependence of polarization out-of-eclipse shows a superposition of two different mechanisms of polarization. We assume that one of them is interstellar polarization while the other one is scattering by electrons in the gas shell of the system. Assuming that the polarization caused by electron scattering does not depend on the wavelength and the wavelength dependence of the interstellar polarization fits the Serkowski law, one can derive the most probable parameters of both the components. It is shown that the proper polarization is 0.3 +/- 0.03%. The UBVRI photometry was also performed. (C) 2004 Elsevier Ltd. All rights reserved.