Speaker
Description
A broadband study of high-z (z>3) blazars enables us to understand the evolution of the properties of relativistic jets over cosmic time. Moreover, it has been found in many studies that such high-z blazars host extremely massive black holes (M$_{BH}$> 1e9 M$_{\odot}$) and thus shed a new light on the formation of supermassive black holes in the early Universe. Here we report the first detection of $\gamma$-ray emitting blazars beyond z=3.1 using the sensitive Pass 8 dataset of $Fermi$-LAT. They are found to host extremely massive black holes at their centers, as confirmed from both IR-UV continuum modeling with a standard accretion disk and also with the emission line measurements using optical spectroscopy. Further details of the results will be presented within the framework of the disk-jet connection in powerful jetted AGNs.
