Magnetic reconnection and Blandford–Znajek process around rotating black holes. Issue 4 (28th May 2018)

• Record Type: Journal Article
• Authors: Singh, Chandra B; Garofalo, David; de Gouveia Dal Pino, Elisabete M
• Is Part Of: Monthly notices of the Royal Astronomical Society. Volume 478:Issue 4(2018)
• Page Start: 5404
• Page End: 5409
• Publication Date: 2018-05-28
• Subjects: accretion, accretion discs -- black hole physics -- galaxies: jets -- X-rays: binaries; Astronomy -- Periodicals; Periodicals; 520.5
• DOI: 10.1093/mnras/sty1405
• Languages: English
• ISSNs: 0035-8711

Abstract

ABSTRACT: We provide a semi-analytic comparison between the Blandford–Znajek (BZ) and the magnetic reconnection power for accreting black holes in the curved space–time of a rotating black hole. Our main result is that for a realistic range of astrophysical parameters, the reconnection power may compete with the BZ power. The field lines anchored close to or on the black hole usually evolve to open field lines in general relativistic magnetohydrodynamic (GRMHD) simulations. The BZ power is dependent on the black hole spin while magnetic reconnection power is independent of it for the force-free magnetic configuration with open field lines adopted in our theoretical study. This has obvious consequences for the time evolution of such systems particularly in the context of black hole X-ray binary state transitions. Our results provide analytical justification of the results obtained in GRMHD simulations.