English

Double Compton and Cyclo-Synchrotron in Super-Eddington Disks, Magnetized Coronae, and Jets

High Energy Astrophysical Phenomena 2017-04-26 v2 General Relativity and Quantum Cosmology

Abstract

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 r15rgr\sim 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 T109T\sim 10^9K is 100\sim 100 times higher than the disk's black body temperature. Our results show the importance of double Compton and synchrotron in super-Eddington disks, magnetized coronae, and jets.

Keywords

Cite

@article{arxiv.1608.08627,
  title  = {Double Compton and Cyclo-Synchrotron in Super-Eddington Disks, Magnetized Coronae, and Jets},
  author = {Jonathan C. McKinney and Jens Chluba and Maciek Wielgus and Ramesh Narayan and Aleksander Sadowski},
  journal= {arXiv preprint arXiv:1608.08627},
  year   = {2017}
}

Comments

25 pages, 14 figures, 3 tables, submitted to MNRAS