Systematic two-dimensional radiation-hydrodynamic simulations of super-Eddington accretion flow and outflow: Comparison with the slim disk model

To what extent can the one-dimensional slim disk model reproduce the multi-dimensional results of global radiation-hydrodynamic simulations of super-Eddington accretion? With this question in mind, we perform systematic simulation study of accretion flow onto a non-spinning black hole for a variety of black hole masses of (10-10(7)) M-circle dot and mass accretion rates of (1.4 x 10(2)-5.6 x 10(3)) L-Edd/c(2) (with L-Edd and c being the Eddington luminosity and speed of light). In order to adequately resolve large-scale outflow structure, we extensively expand a simulation box to cover the space of 3000 r(S) (with r(S) being the Schwarzschild radius), larger than those in most previous studies, so that we can put relatively large angular momentum to the gas injected from the outer simulation boundary. The adopted Keplerian radius, at which the centrifugal force balances with the gravitational force, is r(K) = 300 r(S). The injected mass first falls and is accumulated at around this radius and then slowly accretes towards the central black hole via viscosity. We simulate such accretion processes, taking inverse and bulk Compton scattering into account. The simulated accretion flow is in a quasi-steady state inside r(qss) similar to 200 r(S). Within this radius the flow properties are, as a whole, in good agreement with those described by the slim disk model except that the radial density profile of the underlying disk is much flatter, rho proportional to r(-0.73) (cf. rho proportional to r(-3/2) in the slim disk model), due probably to efficient convection. We find very weak outflow from inside r similar to 200 r(S) unlike the past studies.