An Analytic Model For Magnetically-Dominated Accretion Disks

• DOI: 10.21105/astro.2310.04507
• Publication Date: 2024-03-18T11:19:51Z
• Authors: Philip F. Hopkins; Jonathan Squire; Eliot Quataert; Norman Murray; Kung-Yi Su; Ulrich P. Steinwa...; Kyle Kremer; Claude-Andre Fauc...; Sarah Wellons
• Keywords: Accretion disc

Recent numerical cosmological radiation-magnetohydrodynamic-thermochemical-star formation simulations have resolved the of quasar accretion disks with Eddington or super-Eddington rates onto supermassive black holes (SMBHs) down to a few hundred gravitational radii. These 'flux-frozen' and hyper-magnetized appear be qualitatively distinct from classical $\alpha$ magnetically-arrested disks: midplane pressure is dominated by toroidal magnetic fields plasma $\beta \ll 1$ powered advection flux interstellar medium (ISM), they are super-sonically trans-Alfvenically turbulent cooling times short compared dynamical yet remain gravitationally stable owing support. In this paper, we present simple analytic similarity model for such disks. For reasonable assumptions, entirely specified boundary conditions (inflow rate at BH radius influence [BHROI]). We show that scalings robust various detailed agree remarkably well (given their simplicity), demonstrate self-consistency stability even in outer disk (approaching BHROI) hyper-Eddington rates. <em>Animations referred paper can viewed <a href="http://www.tapir.caltech.edu/~phopkins/Site/animations/Movies_zoom.html">here</a>.</em>