Black Hole Flares: Ejection of Accreted Magnetic Flux through 3D Plasmoid-mediated Reconnection
Journal Article
·
· The Astrophysical Journal. Letters
- Flatiron Institute, New York, NY (United States); Princeton University, NJ (United States)
- Harvard University, Cambridge, MA (United States)
- Harvard University, Cambridge, MA (United States); University of Amsterdam (Netherlands)
- University of Amsterdam (Netherlands)
- Flatiron Institute, New York, NY (United States)
- Northwestern University, Evanston, IL (United States)
- University College London (United Kingdom)
Magnetic reconnection can power bright, rapid flares originating from the inner magnetosphere of accreting black holes. We conduct extremely high-resolution (5376 × 2304 × 2304 cells) general-relativistic magnetohydrodynamics simulations, capturing plasmoid-mediated reconnection in a 3D magnetically arrested disk for the first time. We show that an equatorial, plasmoid-unstable current sheet forms in a transient, nonaxisymmetric, low-density magnetosphere within the inner few Schwarzschild radii. Magnetic flux bundles escape from the event horizon through reconnection at the universal plasmoid-mediated rate in this current sheet. The reconnection feeds on the highly magnetized plasma in the jets and heats the plasma that ends up trapped in flux bundles to temperatures proportional to the jet's magnetization. The escaped flux bundles can complete a full orbit as low-density hot spots, consistent with Sgr A* observations by the GRAVITY interferometer. Reconnection near the horizon produces sufficiently energetic plasma to explain flares from accreting black holes, such as the TeV emission observed from M87. The drop in the mass accretion rate during the flare and the resulting low-density magnetosphere make it easier for very-high-energy photons produced by reconnection-accelerated particles to escape. The extreme-resolution results in a converged plasmoid-mediated reconnection rate that directly determines the timescales and properties of the flare.
- Research Organization:
- Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States). Oak Ridge Leadership Computing Facility (OLCF)
- Sponsoring Organization:
- National Science Foundation (NSF); USDOE Office of Science (SC), Basic Energy Sciences (BES). Scientific User Facilities (SUF)
- Grant/Contract Number:
- AC05-00OR22725
- OSTI ID:
- 1983318
- Journal Information:
- The Astrophysical Journal. Letters, Journal Name: The Astrophysical Journal. Letters Journal Issue: 2 Vol. 924; ISSN 2041-8205
- Publisher:
- IOP PublishingCopyright Statement
- Country of Publication:
- United States
- Language:
- English
Similar Records
General-relativistic Resistive Magnetohydrodynamics with Robust Primitive-variable Recovery for Accretion Disk Simulations
Relativistic resistive magnetohydrodynamic reconnection and plasmoid formation in merging flux tubes
The event horizon of M87
Journal Article
·
Sun Sep 08 20:00:00 EDT 2019
· The Astrophysical Journal. Supplement Series (Online)
·
OSTI ID:1593850
Relativistic resistive magnetohydrodynamic reconnection and plasmoid formation in merging flux tubes
Journal Article
·
Wed Feb 06 19:00:00 EST 2019
· Monthly Notices of the Royal Astronomical Society
·
OSTI ID:1612629
The event horizon of M87
Journal Article
·
Mon Jun 01 00:00:00 EDT 2015
· Astrophysical Journal
·
OSTI ID:22883124