ABSTRACT. Radial velocity observations obtained at the Kitt Peak National Observatory in 1981Observatory in , 1983Observatory in , 1984Observatory in , and 1991 and G9 and that the entire d Lib system is even more similar to the archetypal eclipsing binary 0.95 ע 0.04 M , b Persei (Algol) than was previously recognized. The spectroscopic orbital elements for the B9.5 V primary star in the eclipsing system are also updated.
ABSTRACT. CCD spectra were obtained for the late-B and early-A type Algol binaries AI Draconis and V505 Sagittarii during their 1991 May primary eclipses. With these spectra, the Rossiter-McLaughlin rotation effect was observed. The least-squares fit to the rotation effect yielded projected rotational velocities of 85.6±2.1 and 131.8±2.8 km s -1 and barycentric velocities of +5.5±0.4 and -0.8±0.6 km s -1 for AI Dra and V505 Sgr, respectively. Compared to their synchronous values, AI Dra appears to be rotating slightly more slowly while V505 Sgr is rotating considerably faster than expected. The eclipse spectra were also examined for signs of secondary and/or tertiary companions. The third star belonging to the V505 Sgr system which was discovered by Tomkin (1992, ApJ, 387, 631) was easily recognized but no absorption features were found that could be directly attributed with any certainty to the secondary in either system. However, the Ca II K line in AI Dra was at times distorted and several weak, broad features were noted in V505 Sgr.
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