Rapid spin changes around a magnetar fast radio burst

Date

2024-02-14

Department

Program

Citation of Original Publication

Hu, Chin-Ping, Takuto Narita, Teruaki Enoto, George Younes, Zorawar Wadiasingh, Matthew G. Baring, Wynn C. G. Ho, et al. ?Rapid Spin Changes around a Magnetar Fast Radio Burst.? Nature 626, no. 7999 (February 2024): 500?504. https://doi.org/10.1038/s41586-023-07012-5.

Rights

This work was written as part of one of the author's official duties as an Employee of the United States Government and is therefore a work of the United States Government. In accordance with 17 U.S.C. 105, no copyright protection is available for such works under U.S. Law.
Public Domain

Abstract

Magnetars are neutron stars with extremely high magnetic fields (≳10¹⁴ gauss) that exhibit various X-ray phenomena such as sporadic subsecond bursts, long-term persistent flux enhancements and variable rotation-period derivative1,2. In 2020, a fast radio burst (FRB), akin to cosmological millisecond-duration radio bursts, was detected from the Galactic magnetar SGR 1935+2154 (refs. 3,4,5), confirming the long-suspected association between some FRBs and magnetars. However, the mechanism for FRB generation in magnetars remains unclear. Here we report the X-ray observation of two glitches in SGR 1935+2154 within a time interval of approximately nine hours, bracketing an FRB that occurred on 14 October 20226,7. Each glitch involved a significant increase in the magnetar’s spin frequency, being among the largest abrupt changes in neutron-star rotation8,9,10 observed so far. Between the glitches, the magnetar exhibited a rapid spin-down phase, accompanied by an increase and subsequent decline in its persistent X-ray emission and burst rate. We postulate that a strong, ephemeral, magnetospheric wind11 provides the torque that rapidly slows the star’s rotation. The trigger for the first glitch couples the star’s crust to its magnetosphere, enhances the various X-ray signals and spawns the wind that alters magnetospheric conditions that might produce the FRB.