Le 15 mai 2018
De 12h45 à 13h45
Kim Venn (University of Victoria)
Analyses of Metal-Poor stars in the CFHT Pristine Survey
The Pristine Survey is a narrow-band photometric survey focused on the metallicity-sensitive Ca H & K lines and conducted in the northern hemisphere with the wide-field MegaCam on the Canada-France-Hawaii Telescope. The main aims of the survey are to uncover a statistical sample of the most metal-poor stars in the Galaxy, to further characterize the smallest Milky Way satellites, and to map the metal-poor substructure in the Galactic halo.
I will present results from our high resolution spectroscopic studies of newly discovered metal-poor stars using the CFHT Espadons spectrograph (and others), including progress in applying our machine learning algorithms (StarNet) to the analysis of optical spectra. Generally, we are finding metal-poor stars with element abundance patterns similar to the published Galactic halo samples, though possibly fewer that are very carbon-rich. These can be compared to supernova yields to investigate their abundance profiles and contribute to studies of the first star initial mass function. The prospects for finding the rare objects, e.g., r-process rich, alpha-challenged, and other chemical peculiarities useful for stellar nucleosynthesis and chemical tagging tests, are exciting.