SEMPARIS – Séminaires en région parisienne Colloquium du
Transcription
SEMPARIS – Séminaires en région parisienne Colloquium du
SEMPARIS – Séminaires en région parisienne http ://string.lpthe.jussieu.fr/semparis/ Colloquium du Département de Physique de l’ENS Jeudi 18 Juin 2015, 13 :30 DPT-PHYS-ENS, Amphitheatre Darboux, Institut Henri Poincare, Paris Domaines : astro-ph Titre : Super-massive black holes reject their food Orateur : Francoise Combes ( Observatoire de Paris ) Résumé : Every galaxy hosts in its center a super-massive black hole (SMBH) of mass between one million and a few billion solar mass. Since the masses of black holes and galaxy bulges are proportional, it is likely that star formation and SMBH feeding occurs simultaneously and that both bulges and SMBH grow in symbiosis. Massive molecular outflows have been recently discovered, in galaxies either actively forming stars or not, but in general showing signs of nuclear activity (AGN). Contrary to previous outflows detected in ionised gas, they contain a large fraction of the gas mass, and are able to impact significantly the evolution of the host galaxy, by regulating or stopping the amount of cold gas available for nuclear star formation, or black hole accretion. Is this evidence of the strong AGN feedback, invoked by galaxy formation models to explain the baryons to dark matter ratios ? or can this regulate the symbiotic bulge and SMBH growth ? The current observations will be reviewed and compared to models.