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This content will become publicly available on March 18, 2026

Title: The Role of Magnetic and Rotation Axis Alignment in Driving Fast Radio Burst Phenomenology
Abstract We propose a scenario that can describe a broad range of fast radio burst (FRB) phenomenology, from nonrepeating bursts to highly prolific repeaters. Coherent radio waves in these bursts are produced in the polar cap region of a magnetar, where magnetic field lines are open. The angle between the rotation and magnetic axes, relative to the angular size of the polar cap region, partially determines the repetition rate and polarization properties of FRBs. We discuss how many of the properties of repeating FRBs—such as their lack of periodicity, energetics, small polarization angle (PA) swing, spectro–temporal correlation, and inferred low source density— are explained by this scenario. The systematic PA swing and the periodic modulation of long-duration bursts from nonrepeaters are also natural outcomes. We derive a lower limit of about 400 on the Lorentz factor of FRB sources applying this scenario to bursts with a linear polarization degree greater than 95%.  more » « less
Award ID(s):
2009619
PAR ID:
10587227
Author(s) / Creator(s):
;
Publisher / Repository:
American Astronomical Society
Date Published:
Journal Name:
The Astrophysical Journal
Volume:
982
Issue:
1
ISSN:
0004-637X
Page Range / eLocation ID:
45
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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