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Rapid spin changes around a magnetar fast radio burst
Chin-Ping Hu1,2, Takuto Narita3, Teruaki Enoto4,5
1Department of Physics, National Changhua University of Education, Changhua City, Taiwan. cphu0821@gm.ncue.edu.tw.
Nature
|February 15, 2024
Summary
Two magnetar glitches, observed in SGR 1935+2154, coincided with a fast radio burst (FRB). These glitches rapidly altered the neutron star
Area of Science:
- * Astrophysics
- * High-energy astrophysics
- * Neutron star physics
Background:
- * Magnetars are neutron stars with ultra-strong magnetic fields (≳1014 Gauss).
- * They exhibit X-ray phenomena like bursts and flux enhancements.
- * The origin of Fast Radio Bursts (FRBs) from magnetars is not fully understood.
Purpose of the Study:
- * To investigate the X-ray behavior of the magnetar SGR 1935+2154 around an FRB event.
- * To understand the magnetar glitch mechanism and its connection to FRB generation.
Main Methods:
- * X-ray observations of the magnetar SGR 1935+2154.
- * Analysis of spin frequency changes and X-ray emission during glitch events.
Main Results:
- * Two significant magnetar glitches were observed within nine hours, bracketing an FRB.
- * Each glitch caused a substantial increase in spin frequency, among the largest recorded for neutron stars.
- * A rapid spin-down phase occurred between glitches, with increased and then decreased X-ray emission and burst rate.
Conclusions:
- * The glitches suggest a coupling between the magnetar's crust and magnetosphere.
- * An ephemeral magnetospheric wind likely caused the rapid spin-down.
- * This wind may alter magnetospheric conditions, potentially triggering FRB events.
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