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تسجيل مستخدم جديدDouble Compton and Cyclo-Synchrotron in Super-Eddington Disks, Magnetized Coronae, and Jets
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Jonathan C. McKinney
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We present an extension to the general relativistic radiation magnetohydrodynamic code HARMRAD to account for emission and absorption by thermal cyclo-synchrotron, double Compton, bremsstrahlung, low-temperature OPAL opacities as well as Thomson and Compton scattering. We approximate the radiation field as a Bose-Einstein distribution and evolve it using the radiation number-energy-momentum conservation equations in order to track photon hardening. We perform various simulations to study how these extensions affect the radiative properties of magnetically-arrested disks accreting at Eddington to super-Eddington rates. We find that double Compton dominates bremsstrahlung in the disk within a radius of $rsim 15r_g$ (gravitational radii) at a hundred times the Eddington accretion rate, and within smaller radii at lower accretion rates. Double Compton and cyclo-synchrotron regulate radiation and gas temperatures in the corona, while cyclo-synchrotron regulates temperatures in the jet. Interestingly, as the accretion rate drops to Eddington, an optically thin corona develops whose gas temperature of $Tsim 10^9$K is $sim 100$ times higher than the disks black body temperature. Our results show the importance of double Compton and synchrotron in super-Eddington disks, magnetized coronae, and jets.
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