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Single-lined Spectroscopic Binary Star Candidates in the RAVE Survey
Repeated spectroscopic observations of stars in the RAdial VelocityExperiment (RAVE) database are used to identify and examine single-linedbinary (SB1) candidates. The RAVE latest internal database (VDR3)includes radial velocities, atmospheric parameters, and other parametersfor approximately a quarter of a million different stars with slightlyless than 300,000 observations. In the sample of ~20,000 stars observedmore than once, 1333 stars with variable radial velocities wereidentified. Most of them are believed to be SB1 candidates. The fractionof SB1 candidates among stars with several observations is between 10%and 15% which is the lower limit for binarity among RAVE stars. Due tothe distribution of time spans between the re-observation that is biasedtoward relatively short timescales (days to weeks), the periods of theidentified SB1 candidates are most likely in the same range. Because ofthe RAVE's narrow magnitude range most of the dwarf candidates belong tothe thin Galactic disk while the giants are part of the thick disk withdistances extending to up to a few kpc. The comparison of the list ofSB1 candidates to the VSX catalog of variable stars yielded severalpulsating variables among the giant population with radial velocityvariations of up to few tens of km s-1. There are 26 matchesbetween the catalog of spectroscopic binary orbits (S_{B^9}) and thewhole RAVE sample for which the given periastron time and the time ofRAVE observation were close enough to yield a reliable comparison. RAVEmeasurements of radial velocities of known spectroscopic binaries areconsistent with their published radial velocity curves.
| Photoelectric radial velocities, Paper XVII The orbits of 30 spectroscopic binaries in the southern Clube Selected Areas
Three of the six southern Clube Areas that were mainly observed at theEuropean Southern Observatory and whose principal results are given inPaper XVI are marginally observable from Haute-Provence. Additionalmeasurements obtained on several observing runs there enabled orbits tobe determined (in most cases rather poorly, owing to the paucity ofdata) for 30 of the newly discovered spectroscopic-binary systems; theyare presented in this paper. One object, HD 33978, seems to be of suchsignificance that special efforts have been made, largely by Drs J.Andersen and H. Lindgren, to obtain additional radial-velocitymeasurements. That system is shown to be a double-lined binary with aperiod of only 10.67 d despite one of its components being a late-typegiant. The giant star has a projected rotational velocity of almost 40km s-1 it could be expected to exhibit RS CVn-typephotometric variations, which have not yet been observed, in addition tothe `ellipsoidal variation', discovered by Hipparcos, which occasionedits designation as VV Lep.
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