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Title: Three-dimensional Simulations of the Magnetorotational Instability in Eccentric Disks
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–Sunyaevαparameter, remains ∼10−2, 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.

 
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PAR ID:
10543901
Author(s) / Creator(s):
; ;
Publisher / Repository:
DOI PREFIX: 10.3847
Date Published:
Journal Name:
The Astrophysical Journal
Volume:
973
Issue:
2
ISSN:
0004-637X
Format(s):
Medium: X Size: Article No. 103
Size(s):
Article No. 103
Sponsoring Org:
National Science Foundation
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