Résumé / Abstract Journal-club_Galaxies

Journal-club Galaxies

« Understanding galaxy formation using the luminosity gap in galaxy groups and clusters »

Habib Khosroshahi
Inst. Theoretical Physics Mathematics (IPM) (Téhéran, Iran)

Majority of galaxies reside in groups and clusters where they are
understood to evolve also through galaxy-galaxy interactions. Multiple
mergers at the core of galaxy groups can develop a luminosity deficiency
or gap, which is quantified as the difference between the luminosity of the
two brightest galaxies in groups and clusters. This observable carries
important information about the evolution of galaxy groups, for instance,
there are indications that collapsed groups with a large luminosity gap,
known as fossil groups, are associated with the halos that are relatively
old. In a series of recent studies, employing X-ray, optical and radio
observations complemented by cosmological simulations, we have utilised
the luminosity gap to probe the formation scenarios for galaxies and specially
the most luminous galaxies in groups and clusters, introduce a powerful
age-date routine for galaxy groups, and also obtain clues about the AGN
activities and the IGM heating.
jeudi 30 octobre 2014 - 11:30
Salle 281, Institut d'Astrophysique
Pages web du journal-club / Journal-club's webpage