Speaker： Dr. Francesco Shankar
德国马普天体物理所 (MPA）
Title: Constraining Black Hole and Galaxy Evolution
Abstract: Supermassive black holes (SMBHs) seem to be ubiquitous at the center of all galaxies which have been observed with high enough sensitivity with HST. SMBH masses are tightly linked with the masses and velocity dispersions of their host galaxies. Also, SMBHs are considered to be the central engines of active galactic nuclei (AGN). It is however still unclear how SMBHs have grown and if they have co-evolved with their hosts. In my talk I will derive, in ways independent of specific models, constraints on how SMBHs must have evolved within their dark matter halos. I will describe the accretion history of SMBHs from z~6 to z~0 by interconnecting a variety of data sets, including the AGN luminosity function, their clustering properties, and Eddington ratio distributions. I‘ll show results obtained through a novel numerical code which evolves the SMBH mass function and clustering adopting broad distributions of Eddington ratios. I will finally insert SMBH evolution in a wider cosmological framework for galaxy evolution constrained directly from the Sloan Digital Sky Survey Data.
Speaker： Dr. Raul Angulo
德国马普天体物理所 (MPA）
Title: Halo assembly histories in a neutralino-CDM cosmology
Abstract: We use the Extended-Press-Schechter (EPS) formalism to study halo assembly histories in a standard $\Lambda$CDM cosmology. A large ensemble of Monte Carlo random walks provides the {\it entire} halo membership histories of a representative set of dark matter particles, which we assume to be neutralinos. I will investigate the first generation halos in terms of their mass and redshift as well as their posterior mass accretion histories. I will also present results regarging the number of accretion events that a typical DM particle has undergone during its life.
Time：Feb. 19, Thursday, at 3:30pm
Place：NAOC seminar room A408
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