Numerical Simulation of Magnetic Reconnection around a Black Hole

• Published in: The Astrophysical journal Vol. 883; no. 1; pp. 69 - 77
• Main Authors: Inda-Koide, Mika, Koide, Shinji, Morino, Ryogo
• Format: Journal Article
• Language: English
• Published: Philadelphia The American Astronomical Society 20.09.2019; IOP Publishing
• Subjects: Astrophysics; black hole physics; Black holes; Computational fluid dynamics; Computer simulation; Electrical resistivity; Fluid flow; Galaxy: nucleus; Magnetic fields; Magnetic reconnection; Magnetohydrodynamics; Mathematical models; methods: numerical; Numerical simulations; plasmas; Reynolds number; Shock waves; stars: black holes
• ISSN: 0004-637X; 1538-4357; 1538-4357
• DOI: 10.3847/1538-4357/ab345f

We performed numerical simulations of general relativistic magnetohydrodynamics with uniform resistivity to investigate the occurrence of magnetic reconnection in a split-monopole magnetic field around a Schwarzschild black hole. We found that magnetic reconnection happens near the black hole at its equatorial plane. The magnetic reconnection has a point-like reconnection region and slow shock waves, as in the Petschek reconnection model. The magnetic reconnection rate decreases as the resistivity becomes smaller. When the global magnetic Reynolds number is 104 or larger, the magnetic reconnection rate increases linearly with time from 2τS to ∼10τS (τS = rS/c, rS is the Schwarzschild radius and c is the speed of light). The linear increase of the reconnection rate agrees with the magnetic reconnection in the Rutherford regime of the tearing mode instability.