Multiple populations in Globular Clusters in the era of JWST

Rome Joint Astrophysics Colloquium - Antonino Milone (University of Padua) - Multiple populations in Globular Clusters in the era of JWST - 16/11/2022
The Rome JAC is a joint initiative of the Physics Dept. of the Tor Vergata University of Rome, INAF - Astronomical Observatory of Rome, and INAF - Institute for Space Astrophysics and Planetology.
Abstract
The color-magnitude diagrams of Globular Clusters (GCs) are composed of multiple sequences that can be followed continuously along the main stellar
evolutionary phases. These sequences correspond to distinct stellar populations with different chemical compositions, which are born at high redshift and keep the memory of the formation environment. In this talk, I
review the multiple population phenomenon and present new results from our ongoing surveys with the Hubble Space Telescope. I share new results, based on the so-called 'chromosome maps' of GCs, that shed light on the primordial clouds from which the first generations of GC stars formed. I discuss the implication of the recent discoveries on multiple populations on the formation history of GCs, their role in the assembly of the Galactic
halo, and possibly, in the reionization of the Universe. Finally, I tentatively predict the impact of the James Webb Space Telescope in the field.