Radial Velocity Studies of Close Binary Stars. XI.

Abstract

Radial-velocity measurements and sine-curve fits to the orbital radial velocity variations are presented for ten close binary systems: DU Boo, ET Boo, TX Cnc, V1073 Cyg, HL Dra, AK Her, VW LMi, V566 Oph, TV UMi and AG Vir. By this contribution, the DDO program has reached the point of 100 published radial velocity orbits. The radial velocities have been determined using an improved fitting technique which uses rotational profiles to approximate individual peaks in broadening functions.Three systems, ET Boo, VW LMi and TV UMi, were found to be quadruple while AG Vir appears to be a spectroscopic triple. ET Boo, a member of a close visual binary with P vis = 113 years, was previously known to be a multiple system, but we show that the second component is actually a close, non-eclipsing binary. The new observations enabled us to determine the spectroscopic orbits of the companion, non-eclipsing pairs in ET Boo and VW LMi. The particularly interesting case is VW LMi, where the period of the mutual revolution of the two spectroscopic binaries is only 355 days.While most of the studied eclipsing pairs are contact binaries, ET Boo is composed of two double-lined detached binaries and HL Dra is single-lined detached or semi-detached system. Five systems of this group were observed spectroscopically before: TX Cnc, V1073 Cyg, AK Her (as a single-lined binary), V566 Oph, AG Vir, but our new data are of much higher quality than the previous studies.

Physical parameters of some close binaries: ET Boo, V1123 Tau, V1191 Cyg, V1073 Cyg and V357 Peg

“…They detected a positive O'Connell effect in Kondo (1966)'s light curves while a negative O'Connell effect was observed by Sezer (1993). Pribulla and Rucinski (2006) and Rucinski et al (2007) could not detect an additional component using adaptive optics observations. The system is also defined as an A-subtype of W UMa systems (Pribulla et al, 2006).…”

“…During the light curve analyses, the PHOEBE graphical user interface developed by Prsa and Zwitter (2005) to visualize the well known Wilson-Devinney (WD) light curve analysis code (Wilson and Devinney, 1971) was used. The adjustable parameters are the inclination i, the non-dimensional potentials (Ω h,c ), the surface temperature of the components (T ph ) and the relative monochromatic luminosities (L) in each passband.…”

“…The radial velocity (RV) data of all systems were taken from the series of papers on "Radial Velocity Studies of Close Binary Stars" by Rucinski and his collaborators. RV data of ET Boo and V1073 Cyg were taken from Pribulla et al (2006), and RV data of V1123 Tau, V1191 Cyg, and of V357 Peg were taken from Rucinski et al (2008). The goodness of fits Σ(O − C) 2 to the light curves were checked for every run.…”

“…• 2190, HIP 73346, 2MASS J14592031 + 4649036) is a β Lyr type eclipsing binary, which is also a member of a quadruple system (Pribulla et al, 2006), and found to be a close visual binary system in 1978 by Couteau (1981). The spectral type of the system was given as F8 by Bartkevičius and Gudas (2002).…”

The Broadening Functions Technique

“…The DDO program was described at the Brno and Mykonos symposia on binary stars (Rucinski 2010a(Rucinski , 2010b. (Pribulla et al 2006) paper showing results at orbital quadratures for ten W UMa systems. Among these binaries, one is a triple and four are quadruple systems.…”