Hyper-luminous Dust Obscured Galaxies discovered by the Hyper
  Suprime-Cam on Subaru and WISE
  We present the photometric properties of a sample of infrared (IR) bright
dust obscured galaxies (DOGs). Combining wide and deep optical images obtained
with the Hyper Suprime-Cam (HSC) on the Subaru Telescope and all-sky mid-IR
(MIR) images taken with Wide-Field Infrared Survey Explorer (WISE), we
discovered 48 DOGs with $i - K_\mathrm{s} > 1.2$ and $i - [22] > 7.0$, where
$i$, $K_\mathrm{s}$, and [22] represent AB magnitude in the $i$-band,
$K_\mathrm{s}$-band, and 22 $\mu$m, respectively, in the GAMA 14hr field
($\sim$ 9 deg$^2$). Among these objects, 31 ($\sim$ 65 %) show power-law
spectral energy distributions (SEDs) in the near-IR (NIR) and MIR regime, while
the remainder show a NIR bump in their SEDs. Assuming that the redshift
distribution for our DOGs sample is Gaussian, with mean and sigma $z$ = 1.99
$\pm$ 0.45, we calculated their total IR luminosity using an empirical relation
between 22 $\mu$m luminosity and total IR luminosity. The average value of the
total IR luminosity is (3.5 $\pm$ 1.1) $\times$ $10^{13}$ L$_{\odot}$, which
classifies them as hyper-luminous infrared galaxies (HyLIRGs). We also derived
the total IR luminosity function (LF) and IR luminosity density (LD) for a
flux-limited subsample of 18 DOGs with 22 $\mu$m flux greater than 3.0 mJy and
with $i$-band magnitude brighter than 24 AB magnitude. The derived space
density for this subsample is log $\phi$ = -6.59 $\pm$ 0.11 [Mpc$^{-3}$]. The
IR LF for DOGs including data obtained from the literature is well fitted by a
double-power law. The derived lower limit for the IR LD for our sample is
$\rho_{\mathrm{IR}}$ $\sim$ 3.8 $\times$ 10$^7$ [L$_{\odot}$ Mpc$^{-3}$] and
its contributions to the total IR LD, IR LD of all ultra-luminous infrared
galaxies (ULIRGs), and that of all DOGs are $>$ 3 %, $>$ 9 %, and $>$ 15 %,
respectively.
