Unraveling the assembly history of the Milky Way using asteroseismology and zoom-in simulations
The study of the formation and evolution of the Milky Way is of paramount importance to modern astrophysics. It holds the key to understanding the near field cosmology and more broadly the universe. Over the past couple of decades, the computational advancements in terms of resources and numerical methods have led to the development of realistic magneto-hydrodynamical zoom-in simulations of the formation of Milky Way mass galaxies in the full cosmological context. On the other hand, we have recently acquired rich observational stellar data through spectroscopy, astrometry, photometry and asteroseismology for a significant fraction of the whole sky from various ground- and space-based instruments. These provide us an unparalleled opportunity to unravel the assembly history of the Milky Way.
In this research project, we have developed a novel framework in which we address the challenging task of making systematic and unbiased comparisons between the rich contemporary observations and the state-of-the-art hydrodynamical simulations of the Milky Way. We demonstrate that, although simulations predict certain chemical and kinematic aspects reasonably well, there are also significant discrepancies, unveiling the shortcoming in the galaxy formation models which require further investigation. Our results suggest that stars as old as the Sun could have moved radially in or out from their birth locations by about 2 kpc, highlighting the importance of a phenomenon known as radial stellar migration.
This blog is based on one of my research article which was published in 2021 in Monthly Notices of the Royal Astronomical Society (publicly available on arXiv). The article is titled "An observational testbed for cosmological zoom-in simulations: constraining stellar migration in the solar cylinder using asteroseismology".