Constrain Galaxy Formation Physics from Large-Scale Structure Measurements and Weak Lensing

Tue, December 01, 2015

Cosmology seminar event image

Galaxy formation is one of the most intractable phenomena in astrophysics due to the enormous complexity and diversity in the assembly histories of individual galaxies. Modern galaxy surveys provide a unique avenue to understanding galaxy formation physics in a statistical context, through various large-scale structure measurements and the weak gravitational lensing of large numbers of galaxies. I will introduce a new probabilistic framework, called the "iHOD" model, which enables strong constraints on the stellar-to-halo mass relation and the underlying driver for the quenching of star formation in galaxies probed by the Sloan Digital Sky Survey. I will also highlight the advantages of the iHOD model by comparing it with traditional HOD and SHAM methods, as well as an age-matching model in which galaxy quenching depends on halo age at fixed stellar mass. Lastly I will discuss the prospect of extending the iHOD framework to constrain the curious effect of "galaxy assembly bias" using marked statistics.