Stars, gas and dust in elliptical galaxies

TL;DR

This paper discusses recent theoretical models of elliptical galaxy formation, emphasizing the role of mass in chemical evolution and demonstrating how models can reproduce diverse observational data across different wavelengths.

Contribution

It introduces a comprehensive approach combining chemodynamical and semi-analytic models to explain the formation and evolution of elliptical galaxies, highlighting the mass-dependent timescales.

Findings

Massive galaxies reach high metallicity in 0.5 Gyr.

Outer regions of galaxies form stars and develop winds faster than cores.

Models successfully reproduce observations from X-ray to infrared.

Abstract

I will present recent theoretical results on the formation and the high redshift assembly of spheroids. These findings have been obtained by utilising different and complementary techniques: chemodynamical models offer great insight in the radial abundance gradients in the stars; while state semi-analytic codes implementing a detailed treatment of the chemical evolution allow an exploration of the role of the galactic mass in shaping many observed relations. The results will be shown by following the path represented by the evolution of the mass-metallicity relation in stars, gas and dust. I will show how, under a few sensible assumptions, it is possible to reproduce a large number of observables ranging from the Xrays to the Infrared. By comparing model predictions with observations, we derive a picture of galaxy formation in which the higher is the mass of the galaxy, the shorter are the infall and the star formation timescales. Therefore, the stellar component of the most massive and luminous galaxies might attain a metallicity Z > Z_sun in only 0.5 Gyr. Each galaxy is created outside-in, i.e. the outermost regions accrete gas, form stars and develop a galactic wind very quickly, compared to the central core in which the star formation can last up to ~ 1.3 Gyr.