This loads a font easier to read for people with dyslexia.
This renders the document in high contrast mode.
This renders the document as white on black
This can help those with trouble processing rapid screen movements.
The Australia Telescope National Facility Colloquium
15:00-16:00 Fri 05 Jul 2013

Mark Lacy


Mid-infared AGN and the true nature of the quasar population -- Mark Lacy Colloquium

I describe the results of a survey for AGN and quasars selected on the basis of mid-infrared colours. This survey is able to find both obscured and unobscured objects, approximately matched in mid-infrared luminosity over a wide range in luminosity from Seyferts to the most luminous quasars, and with redshifts up to 4.3. The survey consists of 672 objects with classifications and spectroscopic redshifts. I discuss the demographics of the AGN and quasar population revealed by this study, showing that the obscured quasar population continues to comprise at least 50% of the quasar population even at the highest quasar luminosities and redshifts. I will also discuss the radio, far-infrared, emission line and X-ray properties of the AGN and the insights they can give us into the nature of the obscured quasar population. Finally, I will describe how we might start to search for the massive, high redshift galaxies that might correspond to the hosts of these objects in a quiescent phase using the SERVS near-infrared survey with warm Spitzer.


Sebastian Haan

Other Colloquia
What's On