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Photon trapping and outflow are two key physics associated with thesupercritical accretion flow. We investigate the conflict between these twoprocesses based on two-dimensional radiation-hydrodynamic (RHD) simulation dataand construct a simplified (radially) one-dimensional model. Mass loss due tooutflow, which is not considered in the slim-disk model, will reduce surfacedensity of the flow, and if very significant, it will totally suppress photontrapping effects. If the photon trapping is very significant, conversely,outflow will be suppressed because radiation pressure force will be reduced. Tosee what actually occurs, we examine the RHD simulation data and evaluate theaccretion rate and outflow rate as functions of radius. We find that the formermonotonically decreases, while the latter increases, as the radius decreases.However, the former is kept constant at small radii, inside severalSchwarzschild radii, since the outflow is suppressed by the photon trappingeffects. To understand the conflict between the photon trapping and outflow ina simpler way, we model the radial distribution of the accretion rate from thesimulation data and build up a new (radially) one-dimensional model, which issimilar to the slim-disk model but incorporates the mass loss effects due tothe outflow. We find that the surface density (and, hence, the optical depth)is much reduced even inside the trapping radius, compared with the case withoutoutflow, whereas the effective temperature distribution hardly changes. Thatis, the emergent spectra do not sensitively depend on the amount of massoutflow. We conclude that the slim-disk approach is valid for interpretingobservations, even if the outflow is taken into account.

Modified Slim-Disk Model Based on Radiation-Hydrodynamic Simulation Data: The Conflict Between Outflow and Photon Trapping