Radial velocity studies of close binary stars. XIII

Abstract

Radial velocity (RV) measurements and sine-curve fits to the orbital RV variations are presented for ten close binary systems: EG Cep, V1191 Cyg, V1003 Her, BD+7°3142, V357 Peg, V407 Peg, V1123 Tau, V1128 Tau, HH UMa, and PY Vir. While most of the studied eclipsing systems are contact binaries, EG Cep is a detached or a semidetached double-lined binary and V1003 Her is a close binary of an uncertain type seen at a very low inclination angle. We discovered two previously unknown triple systems, BD+7°3142 and PY Vir, both with late spectral-type (K2V) binaries. Of interest is the low mass-ratio (q = 0.106) close binary V1191 Cyg showing an extremely fast period increase; the system has a very short period for its spectral type and shows a W-type light curve, a feature rather unexpected for such a low mass-ratio system. © 2008. The American Astronomical Society. All rights reserved.