1210.6668 (Manda Banerji et al.)

Hyper-luminous Reddened Broad-Line Quasars at z~2 from the VISTA Hemisphere Survey and WISE All Sky Survey    [PDF]

Manda Banerji, Richard G. McMahon, Paul C. Hewett, Eduardo Gonzalez-Solares, Sergey E. Koposov

We present the first sample of spectroscopically confirmed heavily reddened broad-line quasars selected using the new near infra-red VISTA Hemisphere Survey and \textit{WISE} All-Sky Survey. Observations of four candidates with $(J-K)>2.5$ and $K\le16.5$ over $\sim$180 deg$^2$, leads to confirmation that two are highly dust-reddened broad-line Type 1 quasars at z$\sim$2. The typical dust extinctions are A$_V\sim$2--2.5 mags. We measure black-hole masses of $\sim10^{9}$M$_\odot$ and extinction corrected bolometric luminosities of $\sim10^{47}$ erg/s, making these among the brightest Type 1 quasars currently known. Despite this, these quasars lie well below the detection limits of wide-field optical surveys like the SDSS with $i_{AB}>22$. We also present \textit{WISE} photometry at 3--22$\mu$m, for our full sample of spectroscopically confirmed reddened quasars including those selected from the UKIDSS Large Area Survey (Banerji et al. 2012a). We demonstrate that the rest-frame infrared SEDs of these reddened quasars are similar to UV-luminous Type 1 quasars with significant hot dust emission and starburst quasar hosts like Mrk231. The average 12$\mu$m flux density of our reddened quasars is similar to that of the recently discovered HyLIRG \textit{WISE}1814+3412 ($z=2.452$) at similar redshifts, with two of our reddened quasars also having comparable 22$\mu$m flux densities to this extreme HyLIRG. These optically faint, heavily reddened broad-line quasars are therefore among the most mid infrared luminous galaxies at $z\sim2$, now being discovered using \textit{WISE}

View original: http://arxiv.org/abs/1210.6668