סמינר באסטרונומיה ובאסטרופיזיקה: Collisional Dynamics in the Faintest Galaxies

Zoom: https://tau-ac-il.zoom.us/j/81850414917?pwd=hOoiUteqh6KKoO6pzUfM8jmYjZJWZP.1

Abstract:

Guided by the recent discoveries of faint Milky Way satellites with structural properties lying at the interface between the ultra faint galaxy and globular cluster regimes, I will discuss how "micro galaxies" can be distinguished observationally from self gravitating star clusters, and how these systems may help constrain properties of dark matter. Micro galaxies are a natural prediction of Cold Dark Matter (CDM) cosmology: the high central densities of CDM subhaloes render them remarkably resilient to tidal stripping. Heavily stripped tidal remnants of past Milky Way accretion events may therefore survive even in the strong tidal field of the inner Galaxy -- giving rise to a population co moving groups of stars, gravitationally supported by a surrounding dark matter subhalo. For this class of objects, I will show how collisional processes between stellar populations and dark matter particles lead to a complex phenomenology that includes stellar mass segregation and the dynamical formation of binary stars, blurring the traditional boundaries between globular cluster dynamics and galactic dynamics.

מארגן הסמינר: ד"ר יהונתן שטרן