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Many analyses have concluded that the accretion disc sizes measured from the microlensing variability of quasars are larger than the expectations from the standard thin disc theory by a factor of $sim4$. We propose a simply model by invoking a strong wind from the disc to flatten its radial temperature profile, which can then reconcile the size discrepancy problem. This wind model has been successfully applied to several microlensed quasars with a wind strength $slesssim1.3$ by only considering the inward decreasing of the mass accretion rate (where $s$ is defined through $dot{M}(R)propto({R}/{R_{0}})^{s}$ ). After further incorporating the angular momentum transferred by the wind, our model can resolve the disc size problem with an even lower wind parameter. The corrected disc sizes under the wind model are correlated with black hole masses with a slope in agreement with our modified thin disc model.
For most of their lifetime, super-massive black holes (SMBHs) commonly found in galactic nuclei obtain mass from the ambient at a rate well below the Eddington limit, which is mediated by a radiatively inefficient, hot accretion flow. Both theory and
We report the discovery of a luminous ultra-soft X-ray excess in a radio-loud narrow-line Seyfert1 galaxy, RXJ1633+4718, from archival ROSAT observations. The thermal temperature of this emission, when fitted with a blackbody, is as low as 32.5(+8.0,
We use thirteen seasons of R-band photometry from the 1.2m Leonard Euler Swiss Telescope at La Silla to examine microlensing variability in the quadruply-imaged lensed quasar WFI 2026-4536. The lightcurves exhibit ${sim},0.2,text{mag}$ of uncorrelate
The gravitationally lensed quasar APM 08279+5255 has the fastest claimed wind from any AGN, with velocities of 0.6-0.7c, requiring magnetic acceleration as special relativisitic effects limit all radiatively driven winds to v<0.3-0.5c. However, this
This letter presents a revised radiative transfer model for the infrared (IR) emission of active galactic nuclei (AGN). While current models assume that the IR is emitted from a dusty torus in the equatorial plane of the AGN, spatially resolved obser