|
First Stars III
Contact:
|
Poster
Title: A Search for Binary Stars at Low Metallicity Author(s): David Lai Abstract: We present our initial results in measuring the companion fraction of metal-poor stars ([Fe/H]<-2.0). We are carrying this out by employing the Lick Observatory planet finding system to make high-precision Doppler observations of these objects. Discovering the binary fraction of metal-poor stars provides important constraints on star formation in the early galaxy. Although it has been shown that a majority of solar type stars are in binaries, it is not clear if this is the case for metal-poor stars. At what metallicities do we expect binary systems to form? Or can binaries form at any metallicity, and if so at what fraction? Although we are cannot be as precise as the planet finders, we are still finding estimated errors of only 50 to 300 m/s, depending on the signal-to-noise of a spectrum and stellar atmophere of the star. At this precision we can be much more complete than previous studies in our search for stellar companions.
|
