"From Stars to Black Holes: Linking Stellar Populations, Supermassive Black Holes, and Stellar Orbits in Early Type Galaxies"

Abstract

Massive early-type galaxies (ETGs) represent the final stages of galaxy evolution within the hierarchical formation framework. They typically host central super-massive black holes (BHs), which co-evolve with their galaxies and offer an excellent opportunity to study their joint growth. Using integral-field spectroscopic data (MUSE, SINFONI) and a combined approach of stellar population modelling and triaxial Schwarzschild orbit-based modelling, we investigated the BH masses and stellar orbital structures of four massive ETGs. Our models account for radially varying stellar mass-to-light ratios driven by gradients in the initial mass function (IMF). From stellar population analysis, we detect super-Salpeter IMFs in galaxy centers and find that IMF variations can change BH mass estimates by 10–30% compared to constant-IMF assumptions. In this talk, I will present our results on stellar populations and SMBHs in ETGs, highlighting how they are linked. I will also discuss how different orbital families shape observed kinematics, trace the assembly histories of ETGs, and reveal the impact of central SMBHs.