Three-dimensional simulations of the magnetorotational instability in eccentric disks
arXiv:2312.06775 · doi:10.3847/1538-4357/ad5d5a
Abstract
Previously we demonstrated that the magnetorotational instability (MRI) grows vigorously in eccentric disks, much as it does in circular disks, and we investigated the nonlinear development of the eccentric MRI without vertical gravity. Here we explore how vertical gravity influences the magnetohydrodynamic (MHD) turbulence stirred by the eccentric MRI. Similar to eccentric disks without vertical gravity, the ratio of Maxwell stress to pressure, or the Shakura--Sunyaev alpha parameter, remains ~0.01, and the local sign flip in the Maxwell stress persists. Vertical gravity also introduces two new effects. Strong vertical compression near pericenter amplifies reconnection and dissipation, weakening the magnetic field. Angular momentum transport by MHD stresses broadens the mass distribution over eccentricity at much faster rates than without vertical gravity; as a result, spatial distributions of mass and eccentricity can be substantially modified in just ~5 to 10 orbits. MHD stresses in the eccentric debris of tidal disruption events may power emission 1 yr after disruption.
15 pages, 10 figures, 4 appendices, published in ApJ
References in corpus (11)
- Array Programming with NumPy
- The Athena++ Adaptive Mesh Refinement Framework: Design and Magnetohydrodynamic Solvers
- A gaseous metal disk around a white dwarf
- General Relativistic Hydrodynamic Simulation of Accretion Flow from a Stellar Tidal Disruption
- Star Formation Around Super-Massive Black Holes
- Disk origin of broad optical emission lines of the TDE candidate PTF09djl
- The rebrightening of a ROSAT-selected tidal disruption event: repeated weak partial disruption flares from a quiescent galaxy?
- Local and global dynamics of eccentric astrophysical discs
- HFQPOs and discoseismic mode excitation in eccentric, relativistic discs. II. Magnetohydrodynamic simulations
- Dynamical structure of highly eccentric discs with applications to tidal disruption events
- Importance of magnetic fields in highly eccentric discs with applications to tidal disruption events