Infrared Colours and Spectral Energy Distributions of Hard X-ray
  Selected Obscured and Compton-thick AGN
  We investigate infrared colours and spectral energy distributions (SEDs) of
338 X-ray selected AGN from Swift-BAT 105-month survey catalogue that have
AKARI detection, in order to find a new selection criteria for Compton-thick
AGN. By combining data from Galaxy Evolution Explore (GALEX), Sloan Digital Sky
Survey (SDSS) Data Release 14 (DR14), Two Micron All Sky Survey (2MASS),
Wide-field Infrared Survey Explorer (WISE), AKARI and Herschel for the first
time we perform ultraviolet (UV) to far-infrared (FIR) SED fitting 158 Swift
BAT AGN by CIGALE and constrain the AGN model parameters of obscured and
Compton-thick AGN. The comparison of average SEDs show while the mid-IR (MIR)
SEDs are similar for the three AGN populations, optical/UV and FIR regions have
differences. We measure the dust luminosity, the pure AGN luminosity and the
total infrared (IR) luminosity. We examine the relationships between the
measured infrared luminosities and the hard X-ray luminosity in the 14-195 keV
band. We show that the average covering factor of Compton-thick AGN is higher
compared to the obscured and unobscured AGN. We present a new infrared
selection for Compton-thick AGN based on MIR and FIR colours ([9$\mu$m -
22$\mu$m]$ > 3.0$ and [22$\mu$m - 90$\mu$m]$ < 2.7$) from WISE and AKARI. We
find two known Compton-thick AGN that are not included in the Swift-BAT sample,
and conclude that MIR colours covering 9.7$\mu$m silicate absorption and MIR
continuum can be a promising new tool to identify Compton-thick AGN.
