Authors: Bruno Giacomazzo, John G. Baker, M. Coleman Miller, Christopher S. Reynolds, James R. van Meter
Date: 27 Mar 2012
Abstract: Coalescing supermassive black hole binaries are produced by the mergers of galaxies and are the most powerful sources of gravitational waves accessible to space-based gravitational observatories. Some such mergers may occur in the presence of matter and magnetic fields and hence generate an electromagnetic counterpart. In this paper we present the first general relativistic simulations of magnetized plasma around merging supermassive black holes using the general relativistic magnetohydrodynamic code Whisky. By considering different magnetic field strengths, going from non-magnetically dominated to magnetically dominated regimes, we explore how magnetic fields affect the dynamics of the plasma and the possible emission of electromagnetic signals. In particular we observe a total amplification of the magnetic field of ~2 orders of magnitude which is driven by the accretion onto the binary and that leads to much stronger electromagnetic signals, more than a factor of 10ˆ4 larger than comparable calculations done in the force-free regime where such amplifications are not possible.
© M. Vallisneri 2012 — last modified on 2010/01/29
Tantum in modicis, quantum in maximis