Service d'astrophysique, CEA Saclay, Orme des merisiers
SF2A- PNC- PNG-
91191
Gif sur Yvette cedex, France
Presentation 1 : Invited
Recycling interstellar and intergalactic material
Pierre-Alain Duc
The presence in the intergalactic/intracluster medium of
preprocessed material of galactic origin is now widely
observed. Large quantities of atomic and molecular gas
were recently detected outside galaxies in groups; surveys
of planetary nebulae revealed that a significant
fraction of the overall stellar component in clusters lies
in the intracluster medium. Metallicity measurements
indicate that the intergalactic medium both locally and
and at high redshift is surprisingly polluted in heavy elements.
The processes by which galaxies may loose material and
feed the IGM are multiple and well known: starbursts and
AGN driven outflows, dynamical removing by tidal forces
or ram pressure. The fate of this expelled material has
however been less studied. I will show that part of it
may, under specific conditions, be recycled to form a new
generation of galaxies.