In order to investigate the growth of super-massive black holes (SMBHs), we construct the black hole mass function (BHMF) and Eddington ratio distribution function (ERDF) of X-ray-selected broadline AGNs at z ∼ 1.4 in the Subaru XMM-Newton Deep Survey (SXDS) field. In this redshift range, a significant part of the accretion growth of SMBHs is thought to be taking place. Black hole masses of X-ray-selected broad-line AGNs are estimated using the width of the broad Mg II line and the 3000Å monochromatic luminosity. We supplement the Mg II FWHM values with the Hα FWHM obtained from our NIR spectroscopic survey. Using the black hole masses of broad-line AGNs at redshifts between 1.18 and 1.68, the binned broad-line AGN BHMF and ERDF are calculated using the V max method. To properly account for selection effects that impact the binned estimates, we derive the corrected broad-line AGN BHMF and ERDF by applying the Maximum Likelihood method, assuming that the ERDF is constant regardless of the black hole mass. We do not correct for the non-negligible uncertainties in virial BH mass estimates. If we compare the corrected broad-line AGN BHMF with that in the local Universe, the corrected BHMF at z = 1.4 has a higher number density above 10 8 M ⊙ but a lower number density below that mass range. The evolution may be indicative of a down-sizing trend of accretion activity among the SMBH population. The evolution of broad-line AGN ERDF from z = 1.4 to 0 indicates that the fraction of broad-line AGNs with accretion rate close to the Eddington-limit is higher at higher redshifts.

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We investigate time-dependent inviscid hydrodynamical accretion flows onto a black hole using numerical simulations. We consider the accretion that consists of hot tenuous gas with low specific angular momentum and cold dense gas with high specific angular momentum. The former accretes continuously and the latter highly intermittently as blobs. The high specific angular momentum gas blobs bounce at the centrifugal barrier and create shock waves. The low specific angular momentum gas is heated at the shock fronts and escapes along the rotation axis. The outgoing gas evolves into pressure-driven jets. Jet acceleration lasts until the shock waves fade out. The total amount of the mass ejection is about 1 − 11% of the mass of the blobs. The jet mass increases when the gas blobs are more massive or have larger specific angular momentum. We get narrower well-collimated jets when the hot continuous flow has a lower temperature. In the numerical simulations we used a finite difference code based on the total variation diminishing scheme. It is extended to include the blackbody radiation and to apply the multi time step scheme for time marching.

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It is widely believed that accretion onto a black hole is the origin of X- and γ-ray emission and jets emerging from AGNs. Since the X- and γ-rays are highly variable, the accretion is also expected to be variable. We investigate highly variable hydrodynamical accretion with numerical simulations.