ASTRONOMISCHE NACHRICHTEN, cilt.325, sa.4, ss.336-342, 2004 (SCI-Expanded)
New photoelectric observations of the eccentric orbit binary CW Cephei have been carried out in B, V and R colours during the 2000 observing season at TUBITAK (The Scientific and Technical Research Council of Turkey) National Observatory. The light curves of the system were analyzed with a nonsynchronous rotation approach using the method of Wilson-Devinney in B, V and R bands, simultaneously. Especially, we used the R band to check for a third light in the solution as distinct from previous studies. But, the third light contribution in the light curves comes out to be almost negligible. In this study, the values of the longitude of periastron (omega) of the system's orbit found in the solutions of the light curves and radial velocity curves were collected and the variation of w with time was investigated. A new value of the apsidal motion velocity has been obtained as omega=0.0582 +/- 0.0011 (deg/cycle), corresponding to an apsidal period U=46 +/- 1 yr.