Special Astrophysics Seminar

Digging for buried quasars with WISE and Planck

Michael DiPompeo

University of Wyoming

Around 50% of quasars are hidden behind thick clouds of gas and dust, obscuring them from view in many wavebands. However, the structure and scale of the obscuring material is currently poorly understood. Studying this population is critical to understanding the history of black hole and structure growth in the Universe, the contribution of quasars to various cosmic backgrounds, and the mutual evolution of quasars and their host galaxies. Obscured quasars are easily identified in the infrared, meaning that the recently-released WISE all-sky data allow identification of large numbers of the obscured quasar population for the first time. This allows us to examine the typical dark matter halo masses of these objects that can help constrain models of obscuration via statistical methods. I will present measurements of the halo masses of obscured and unobscured quasars from two independent methods: the quasar angular autocorrelation function (how quasars cluster around themselves), and a cross-correlation of the quasar density with lensing maps of the CMB from Planck. These two methods are in excellent agreement, and provide the next steps in our understanding of this critical population of quasars.