2016/04/30 by Milton Ruiz, Ryan N. Lang, Vasileios Paschalidis +1 · 229 citations
Physics and Astronomy · #Accretion (finance) #Astrophysical Phenomena and Observations #Astrophysical jet #Black hole (networking) #Dipole #Gamma-ray bursts and supernovae #General relativity #Magnetic dipole #Magnetic field #Magnetohydrodynamic drive #Neutron star #Pulsars and Gravitational Waves Research #X-ray binary #astro-ph.HE #gr-qc
paper · pdf · doi:10.3847/2041-8205/824/1/l6
published in The Astrophysical Journal Letters 824(1), L6 (IOP Publishing) · 6 pages, 3 figures, 1 table, matches published version
arxiv created 2016/06/03 · openalex publication_date 2016/06/03 · arxiv updated 2016/06/15 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/06
ABSTRACT We perform magnetohydrodynamic simulations in full general relativity (GRMHD) of quasi-circular, equal-mass, binary neutron stars that undergo merger. The initial stars are irrotational, n = 1 polytropes and are magnetized. We explore two types of magnetic-field geometries: one where each star is endowed with a dipole magnetic field extending from the interior into the exterior, as in a pulsar, and the other where the dipole field is initially confined to the interior. In both cases the adopted magnetic fields are initially dynamically unimportant. The merger outcome is a hypermassive neutron star that undergoes delayed collapse to a black hole (spin parameter a / M BH ∼ 0.74) immersed in a magnetized accretion disk. About 4000 M ∼ 60( M NS /1.625 M ⊙ ) ms following merger, the region above the black hole poles becomes strongly magnetized, and a collimated, mildly relativistic outflow—an incipient jet—is launched. The lifetime of the accretion disk, which likely equals the lifetime of the jet, is Δ t ∼ 0.1 ( M NS /1.625 M ⊙ ) s. In contrast to black hole–neutron star mergers, we find that incipient jets are launched even when the initial magnetic field is confined to the interior of the stars.