Publications (7)
Carbon deficiencies in the primaries of some classical Algols
C. Ibanoglu, A. Dervisoglu, O. Cakirli +2
The equivalent widths of C II 4267 Ã line were measured for the mass-gaining primary stars of the 18 Algol-type binary systems. The comparison of the EWs of the gainers with t…
Evidence for conservative mass transfer in the classical Algol system Librae from its surface carbon-to-nitrogen abundance ratio
A. Dervisoglu, K. Pavlovski, H. Lehmann +2
Algol-type binary systems are the product of rapid mass transfer between the initially more massive component to its companion. It is still unknown whether the process is conservat…
Is NP Aqr a new near-contact binary?
C. Ibanoglu, O. Cakirli, A. Dervisoglu
We present radial velocities of the double-lined spectroscopic binary NP Aqr. The radial velocities and the optical light curves obtained by Hipparcos and ASAS-3 are analyzed separ…
V1898 Cygni: An interacting eclipsing binary in the vicinity of North America nebula
A. Dervisoglu, Ã. Ãakırlı, C. Ibanoglu +1
We present spectroscopic observations of the double-lined early type eclipsing binary V1898\,Cyg. The radial velocities were obtained by means of the cross-correlation technique. A…
Dynamical parallax, physical parameters and evolutionary status of the components of the bright eclipsing binary α Draconis
K. Pavlovski, C. A. Hummel, A. Tkachenko +13
Altough both components of the bright eclipsing binary Dra having been resolved using long baseline interferometry and the secondary component shown to contribute some 15\% of…
Spectroscopic long-term monitoring of RZ Cas -- Part I: Basic stellar and system parameters
H. Lehmann, A. Dervisoglu, D. E. Mkrtichian +3
RZ Cas is a short-period Algol-type system showing episodes of mass transfer and Delta Sct-like oscillations of its mass-gaining primary component. We analyse high-resolution spect…