Bulut, A.Bulut, I.Cicek, C.Erdem, A.2025-01-272025-01-272017978-0-7354-1483-90094-243Xhttps://doi.org/10.1063/1.4976438https://hdl.handle.net/20.500.12428/2545632nd International Physics Congress of Turkish-Physical-Society (TPS) -- SEP 06-09, 2016 -- Bodrum, TURKEYIn this study, orbital period variations of two eclipsing binary systems (NO Vul and EW Lyr) were discussed. Possible light time effects due to third bodies in these systems were re-examined. The mass function and orbital period of hypothetical third bodies were calculated to be 0.000627 +/- 1.000003 M-circle dot, 26.17 +/- 0.05 years and 0.12682 +/- 0.00003 M-circle dot, 77.23 +/- 0.72 years for NO Vul and EW Lyr, respectively.eninfo:eu-repo/semantics/closedAccessbinarieseclipsinglight-time effectstars: individual: NO Vul and EW LyrConference Object181510.1063/1.4976438N/AWOS:0004352051000942-s2.0-85015992504Q4