The New Era of Galactic Archaeology

Yuan-Sen Ting
July 12, 2018 - 12:15pm

Abstract

Understanding physical processes responsible for the formation and evolution of galaxies like the Milky Way is a fundamental problem in astronomy. However, a key challenge is that the properties and orbits of the stars can only be observed at present: to understand what happened in the Milky Way at earlier epochs, one must explore “archaeological” techniques. The Galactic archaeology landscape is rapidly changing thanks to various on-going large-scale surveys (Gaia, spectroscopy, asteroseismology) which provide a few orders of magnitudes more stars than before. In this talk, I will discuss the new "phenomenological" opportunities with these surveys. In particular, I will present a quantitative constraint on the radial migration of stars, the ISM enrichment history, the vertical heating and stellar cluster mass function of the Milky Way. I will also describe a new set of tools for efficient measuring > 20 elemental abundances from low-resolution R=2000 spectra, for discovering spectroscopically unresolved binaries, and for inferring stellar ages and asteroseismic parameters from low-resolution spectra.