A Comprehensive Photometry of the Eclipsing Binarygo CYG

Observations photometric of the system GO Cyg were obtained in two filters B and V in Observatory of Doctor Mojtahedi at Birjand
University in August and October 2010. Using the data of photometry, light curves of system were analyzed by the phoebe software and its physical and partial geometric parameters have been extracted. Using the results of photometry analysis and half amplitude of the radial velocity curves of components, its absolute parameters have been determined. By examining the O-C curve of the eclipsing
minima of eclipsing binary GO Cyg, new ephemery, mass transfer or mass loss rates of system have been determined. In addition, with attributing the periodic variations of the O-C curve to the light - time effect, the period of triplet system, its orbital parameters, minimum of mass of third body and a semi major axis of triplet system orbit have been determined.