GW170817/GRB170817A has offered unprecedented insight into binary neutron star post-merger systems. Its Prompt and afterglow emission imply the presence of a tightly collimated relativistic jet with a smooth transverse structure. However, it remains unclear whether and how the central engine can produce such structured jets. Here, we utilize 3D general relativistic magnetohydrodynamic simulations starting with a black hole surrounded by a magnetized torus with properties typically expected of a post-merger system. We follow the jet, as it is self-consistently launched, from the scale of the compact object out to more than three orders of magnitude in distance. We find that this naturally results in a structured jet, which is collimated by the disc wind into a half-opening angle of roughly 10°; its emission can explain features of both the prompt and afterglow emission of GRB170817A for a 30° observing angle. Our work is the first to compute the afterglow, in the context of a binary merger, from a relativistic magnetized jet self-consistently generated by an accreting black hole, with the jet’s transverse structure determined by the accretion physics and not prescribed at any point.
- Award ID(s):
- 1911206
- NSF-PAR ID:
- 10299599
- Date Published:
- Journal Name:
- Monthly Notices of the Royal Astronomical Society
- Volume:
- 503
- Issue:
- 3
- ISSN:
- 0035-8711
- Page Range / eLocation ID:
- 4363 to 4371
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1093/mnras/stab723
