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arXiv · 0801.4387

Magnetized Neutron Star Mergers and Gravitational Wave Signals

Matthew Anderson·Eric W. Hirschmann·Luis Lehner·Steven L. Liebling·Patrick M. Motl·David Neilsen·Carlos Palenzuela·Joel E. Tohline
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Abstract

We investigate the influence of magnetic fields upon the dynamics of and resulting gravitational waves from a binary neutron star merger in full general relativity coupled to ideal magnetohydrodynamics (MHD). We consider two merger scenarios, one where the stars begin with initially aligned poloidal magnetic fields and one with no magnetic field. Both mergers result in a strongly differentially rotating object. In comparison to the non-magnetized scenario, the aligned magnetic fields delay the final merger of the two stars. During and after merger we observe phenomena driven by the magnetic field, including Kelvin-Helmholtz instabilities in shear layers, winding of the field lines, and transition from poloidal to toroidal fields. These effects not only produce electromagnetic radiation, but also can have a strong influence on the gravitational waves. Thus, there are promising prospects for studying such systems with both types of waves.

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BibTeXRIS

Matthew Anderson, Eric W. Hirschmann, Luis Lehner, Steven L. Liebling, Patrick M. Motl, David Neilsen, Carlos Palenzuela, Joel E. Tohline. 2008-06-09. Magnetized Neutron Star Mergers and Gravitational Wave Signals. https://doi.org/10.1103/physrevlett.100.191101

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