Metallicity in galaxy groups: numerical simulations and X-ray observations

Abstract

We aim at studying the chemical enrichment of the intergalactic medium in groups of galaxies designing a comparative programme between simulations and observations. This programme will provide insights on the process of chemical recycling between galaxies and in the medium they inhabit and will help to set constrains on galaxy formation models. Because of the complexity and non-linear growth of the structure, sophisticated numerical simulations are the most suitable tools to tackle this problem. We propose to study the formation and evolution of galaxies in groups in the context of the current cosmological paradigm with special interest in those processes such as interactions, mergers, galactic winds, gas starvation, accretion, turbulence which might affect the production and mixing of chemical elements, key ingredients in the regulating the transformation of gas into stars or triggering galactic outflows capable of transporting enriched material into the intergalactic media. We can follow stars in different galaxies since their born time to today, searching for links between their current observed properties and the physical conditions under which they were born, in order to make predictions which might help to interpret observations within the current cosmological paradigm. We will use state-of-art numerical simulations to study the growth of structure in the concordance Lambda Cold Dark Matter (LCDM) cosmology. We have physically-based Supernova (SN) feedback scheme in the massively parallel galaxy formation code GADGET-3. From the observational point of view, we will use X-ray observations of the intragroup gas with the last generation of satellites, XMM-Newton and Chandra. These observations will give us the means to probe the physical state of gas, with measures of density, temperature and metallicity. Whenever we dispose of deep observations, we will be able to compute two-dimensional maps of these quantities. The numerical simulations can be directly compared to the observational results derived from the X-ray observation on the extragalactic gas in groups. (AU)