We investigate the spectral energy distribution (SED) in the super-critical disk accretion flows around the black holes, by solving the multi-frequency radiation transfer as well as the energy equations of radiation and gas. Here, special attention is paid on the photon-trapping effects, that is, photons diffuse towards not only the vertical direction but also radial direction with the accreting gas.By the enhanced photon-trapping, when L ≥ 3LE, the peak frequency of the SED tends to decrease in spite of increase of mass-accretion rate. Since the high-energy photons are generated near the equatorial plane, they are more effectively trapped in the flow than the low-energy ones and the SED shifts to lower-energy side. In comparison with the observational data in the X-ray H-R diagram, we found that the black hole of IC 342 S1, which is an ultraluminous X-ray source (ULXs), is considerably massive, ∼100Modot, and the time variation of IC 342 S1 data can be explained only by the modulation of the mass-accretion rate.
Coevolution of Black Holes and Galaxies
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