Magnetic reconnection: flares and coronal heating in active galactic nuclei

被引:115
作者
Di Matteo, T [1 ]
机构
[1] Univ Cambridge, Inst Astron, Cambridge CB3 0HA, England
关键词
accretion; accretion discs; magnetic fields; MHD; galaxies : active;
D O I
10.1046/j.1365-8711.1998.01950.x
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
A magnetically structured accretion disc corona, generated by buoyancy instability in the disc, can account for observations of flare-like events in active galactic nuclei. We examine how Petschek magnetic reconnection, associated with MHD turbulence, can result in a violent release of energy and heat the magnetically closed regions of the corona up to canonical X-ray emitting temperatures. X-ray magnetic flares, the after effect of the energy released in slow shocks, can account for the bulk of the X-ray luminosity from Seyfert galaxies and consistently explain the observed short-time-scale variability.
引用
收藏
页码:L15 / L20
页数:6
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