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Title: The escape of fast radio burst emission from magnetars
ABSTRACT We reconsider the escape of high-brightness coherent emission of fast radio bursts (FRBs) from magnetars’ magnetospheres, and conclude that there are numerous ways for the powerful FRB pulse to avoid non-linear absorption. Sufficiently strong surface magnetic fields, $$\ge 10{{\ \rm per\ cent}}$$ of the quantum field, limit the waves’ non-linearity to moderate values. For weaker fields, the electric field experienced by a particle is limited by a combined ponderomotive and parallel-adiabatic forward acceleration of charges by the incoming FRB pulse along the magnetic field lines newly opened during FRB/coronal mass ejection. As a result, particles surf the weaker front part of the pulse, experiencing low radiative losses, and are cleared from the magnetosphere for the bulk of the pulse to propagate. We also find that initial mildly relativistic radial plasma flow further reduces losses.  more » « less
Award ID(s):
1903332
PAR ID:
10550119
Author(s) / Creator(s):
Publisher / Repository:
Monthly Notices of the Royal Astronomical Society
Date Published:
Journal Name:
Monthly Notices of the Royal Astronomical Society
Volume:
529
Issue:
3
ISSN:
0035-8711
Page Range / eLocation ID:
2180 to 2190
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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