1. A luminous quasar at a redshift of z = 7.085

2. Mortlock et al., Nature (2011), 474, 7353, 616-619
Bolton et al., MNRAS Letters (2011), 416, 1, 70-74

3. Highest Redshift Quasar
ULAS J
RA 11hr 20m 1.48s, Dec 6deg 41' 24.3”
Identified by United Kingdom Infrared Deep Sky Survey (UKIDSS) on 3rd Sep 2010
Spectra obtained using Gemini Multi-Object Spectrograph on Gemini North Telescope on 27th Nov 2010
Accurate redshift obtained by Si III,
C III and Mg II is
It is a radio-quiet quasar

10. Effective GP Optical Depth

15. GADGET 3 code
Boxsize 10h-1 Mpc
Gas particle mass
100 LOS around haloes with Radiative Transafer
Largest halo mass

16. Ionization Models

21. Two Parameters to Quantify
Proximity zone radius
Transmitted Fraction at rest farme wavelength

23. i) IGM with ~ 0.1 (1.0) neutral fraction with QSO lifetime
ii) A high column density HI system in close proximity of the quasar.
But (i) and (ii) are not mutually exclusive!

24. Problem of BH mass still unresolved!
is still less by a factor of 5 to build up a BH of mass so early!