Projeto Observacional para 2009A - SO2009A-032

Autor: Claudia Mendes de Oliveira
Instituição: IAG
e-mail: oliveira@astro.iag.usp.br

Co-autores:
Raimundo Lopes de Oliveira
Laerte Sodré Jr.

Título: Confirmation of the nature of fossil groups

Resumo: Fossil groups have received a great deal of attention in the past years given that they were recognized as the possible end products of groups and clusters. Fossil groups are systems with one bright elliptical galaxy surrounded by less luminous companions, and which have extended X-rays. The companions to the central elliptical have magnitudes at least 2 magnitudes fainter and therefore the system is dominated by one very massive galaxy that is believed to be the remains of rich groups. Our group at IAG (dos Santos et al. 2007) has catalogued the largest sample of fossil groups so far, from the sdss. However, in this task, mostly photometric redshifts were used. In this project we propose to obtain long slit spectra of a few galaxies in a subsample of fossil groups to confirm their nature.