The multiple dimensions of the Local Group: galactic evolution from structures, chemistry, dynamics and histories of star formation

In force date
Call year
Gallart Gallart
Amount granted to the IAC Consortium
135.520,00 €

This project consists of investigating fundamental questions concerning the formation and evolution of galaxies from the smallest galactic scales to those of large spiral galaxies by adopting the approach of galactic archaeology. By determining the ages, metallicities and kinematics of individual stars, in particular low-mass, whose life-times are longer than a Hubble time, it is possible to reconstruct the way galaxies evolved from the earliest times to the present day. This approach can be applied in its full potential to the Local Group, thanks to the suite of top-level current generation observing facilities such as HST, the VLT and the GTC, to mention a few. The Local Group is a goldmine for resolved stellar population studies of galaxy formation and evolution, as it hosts representatives of all galaxy types, except for a large elliptical. We will perform a detailed characterization of the star formation history and chemo dynamical properties of galactic discs and haloes, in a variety of Local Group galaxy types, from fossil galaxies like the ultra-faint dwarfs, through small disk galaxies like M33 and the Magellanic Clouds, to a large spiral like the Milky Way. We will adopt a comprehensive and multi-faceted approach, in which different techniques such as deep colour-magnitude diagrams, analysis of variable stars, and wide-area multi-object spectroscopy, are used in a complementary way to provide a very detailed view of the observed evolutionary status of the galaxies under examination. Our group has pioneered this type of approach, which has already proven extremely successful and rewarding, as indicated for example by the international recognition our works have earned. In this way, we will be able to tackle questions such as: to what extent internal and environmental processes drive the evolution of the most common type of galaxies, the dwarfs? Do small galactic disks form inside-out? What is the mass threshold for galaxy formation? Do stellar haloes exist also around small disk galaxies? Were stellar halos formed from the shredding of small satellite galaxies, as predicted by Lambda Cold Dark Matter models? To guarantee the success of this project, we are combining the complementary expertise of an international team of researchers specialists in different aspects of resolved stellar population studies to build a team that has all the skills and proven potential necessary for attacking the above problem. We have been awarded large amounts of observing time at top-level observing facilities worldwide, both as leaders and co-investigators of important international collaborations. For example, we are part of a large survey of the Magellanic Clouds, SMASH, which has been awarded 30 nights on the CTIO 4m with DECam, the largest optical camera in the world; we have obtained over 150 hours on the VLT for spectroscopic studies, and are part of two HST proposals which amount to 111 orbits. In this proposal we emphasize the request of the man-power the team needs to guarantee a prompt exploitation of the high quality data-sets acquired, an optimal science return and fulfillment of the international commitments already acquired, while cutting as much as possible in other costs. This project deals with hot-topics in near-field cosmology, attacking them with state-of-the-art data and methodologies. The results of our research are guaranteed to have an international impact, contributing to the scientific excellence of Spain and Europe.

Related projects
A view of our Milky Way galaxy with its close neighbors the Magellanic Clouds
Galaxy Evolution in the Local Group

Galaxy formation and evolution is a fundamental Astrophysical problem. Its study requires “travelling back in time”, for which there are two complementary approaches. One is to analyse galaxy properties as a function of red-shift. Our team focuses on the other approach, called “Galactic Archaeology”. It is based on the determination of galaxy