Wednesday 1^st December 2010 - 3:00 P.M.

Università "La Sapienza" Roma - Sala Touschek (Physics Dept., Old Building - 2nd Floor)

Title: GRB host galaxies studies with X-Shooter@VLT

Abstract: Gamma-ray bursts (GRBs) are the most powerful explosions since the formation of the Universe, associated with the death of massive stars or mergers of compact stellar objects. Several recent striking results strongly support the idea that host galaxies of GRBs are opening a new view on our understanding of galaxy formation and evolution, back to the very primordial universe at z ∼ 8. They form a unique sample of galaxies which cover a wide range of redshift, they are typically weak with low mass and unlike other methods they are not selected on luminosity. In recent years, thanks to the support of new generation instruments, multi-band photometry and spectroscopy allow us to better investigate the properties of these host galaxies (e.g. stellar mass, age, SFR, metallicity ), to study their possible evolution and to compare them with field galaxies and other classes of galaxies. In the future we therefore expect to improve our GRB hosts studies in order to explore the different characteristics for galaxies that host long GRBs and short GRBs that should lead us to a better understanding of the environment in which the GRB event occurred. GRB host spectroscopy is one of the main science drivers behind the X-Shooter spectrograph. In this talk, I will show the state of the art on the study of this type of galaxies and then I will present the first results of the program devoted to Italian-French GTO multiband spectroscopy of GRB host galaxies with X-Shooter.