Observational appearance and spectrum of black hole winds from supercritical accretion discs: scattering effect

Abstract

We investigate the observational appearance of a black hole wind blown off from a supercritical accretion disc, considering the electron scattering, which separates the thermalization surface and the apparent photosphere, especially in the high-energy regime. Similar to the spherical case, the size of the thermalization surface becomes quite smaller than that of the apparent photosphere. In contrast with the spherical case, the shapes of the thermalization surface as well as the apparent photosphere are extremely aspherical. As a result, the expected spectral energy distribution is somewhat flat and soft in the middle and high-energy regimes, except for a small peak of the outer disc origin in the low-energy regime.