GEPI

De la conception instrumentale
à l’exploitation des observables
Accueil > Séminaires > A new formation and evolution (...)

A new formation and evolution scenario of the the Local Group dwarf galaxies

Sylvain Fouquet

Since more than 10 years, the knowledge of the Local Group and especially
of its dwarf galaxies has been quickly developed. Some surveys like the SDSS
or the PAndAS survey have discovered new dwarf galaxies around the MW and
M31. New instruments like the VLT, the KECK and the HST have allowed to resolve
the stars of the dwarf galaxies in order to determine their distance, velocity,
star formation history, etc. In parallel, the cosmological simulations manage to
reach high resolution which allow to make predictions on the dwarf galaxy state
in the environnement of L* galaxies, like the MW.

Several critical incompatibilities arise between the cosmological simulations and the
observations, like the famous "missing satellite problem". To resolve this
problem and matching the new observations, I suggest a new
scenario of the formation and evolution of the Local Group dwarf galaxies.
In this scenario, the dwarf galaxies are not remnants of primordial galaxies but remnants
of tidal dwarf galaxies ejected by a major merger which would have produced M31.

During my talk, I will use 3D animation to better visualize the spatial distribution
of the dwarf galaxies. Bring your 3D glasses if you have them. If you do not have,
I will provide them