Photometric Study of Eclipsing Binary U Sagittae

Abstract

New UBV photometry of Algol type binary star U Sge obtained during 1993 are presented, analyzed, and discussed. Wilson-Devinney code was employed to analyze the light curves. Absolute dimensions of the system were obtained, and positions of both components on H-R diagram were specified. Finally through color curve analysis absolute visual magnitudes were determined.

Further confirmations of mass transfer in Algol type binary U Sagittae

“…Sarna and De Greve (1994) stated that "our solution shows that if the theoretical model is to agree with the observations the present day mass ratio must be around 0.37 (M 1 = 4.45 M sun ) this means that spectroscopic mass ratio (i.e., 0.33) is based on poorly determined semiamplitudes." Except for T1 and T2, the other orbital and physical parameters estimated in this work are in agreement with corresponding parameters of V-filter obtained by Manzoori et al (2006). The temperature difference just mentioned may be attributed to the appearance and disappearance of a variable number of (cool or hot) spots on the surfaces of both components.…”

“…To check the details of pa- rameters estimated and equations used, the reader may refer to Manzoori et al (2006).…”

“…In continuation to our previous works on U Sge (see Manzoori et al 2006;Manzoori and Ghozaliasl 2007), here I do analyze a new V-light curve and compute the physical and orbital parameters of the system. This allows to determine the spots' characteristics and obtain the Roche lobe filling configurations of components using the binary maker W-Dbased program.…”

“…This system was recently studied photometrically by Manzoori et al (2006) who, through color curve analysis, reported excess UV radiations which were attributed to streams of matter falling on the primary B star. The period of the system was also studied by Manzoori and Ghozaliasl (2007).…”

Orbital Period Modulation in SW Cygni

“…A similar phenomenon was also reported by McNamara & Feltz (1976) and Manzoori, Jassur, & Kermani (2006) for other Algols. (d) There is a remarkable deficiency of carbon and overabundance of nitrogen in the secondaries of Algols as compared to single G or K subgiants, as a result of the conversion process of C to N via the CN cycle (Parthasarathy et al 1983).…”