Day 33

Wednesday.  Telecon in an hour.


1106.6088
A luminous quasar at z = 7.085
Mortlock  et al.


At optical wavelengths, quasar search at z>6.5 insensitive since the universe was not fully ionized at that time.  Quasar found (how?) at z=7.085; 6.3e13 L_sun; 2e9 M_sun SMBH; radius of ionization 1.9 Mpc (x1/3 of quasars at z=6.0 - 6.4.  Transmission profile consistent with a Ly alpha damping wing--neutral fraction in front of said quasar is > 0.1


* I guess this is an interesting way to find out the ionization fraction of the universe at different redshifts.


1106.6055
Searching for high-redshift lyman alpha emitters in the COSMOS field with NEWFIRM
Krug, ... Dey, ... Januzzi et al.


Isolate Lya emitters at z=7.7 with a ultra-narrowband filters (~8 and 9 A width).  5 sigma detections of 4 candidate Lya emitters in 2.8e4 Mpc^3.  Construct a luminosity function; compare with z-5.7 and 6.5; Half of these candidates are likely z=7.7 targets, but requires spectro followup to verify the redshift of these candidates.  Results suggest no major evolution in the neutral hydrogen fraction of the IGM between z=3.1 and 7.7, even if only 2 of the candidates are spectroscopically confirmed.