# Magnetar spin-down glitch clearing the way for FRB-like bursts and a pulsed radio episode

**Authors:** G. Younes, M. G. Baring, A. K. Harding, T. Enoto, Z. Wadiasingh, A. B. Pearlman, W. C. G. Ho, S. Guillot, Z. Arzoumanian, A. Borghese, K. Gendreau, E. Gogus, T. Guver, A. J. van der Horst, C. -P. Hu, G. K. Jaisawal, C. Kouveliotou, L. Lin, W. A. Majid  
**arXiv:** [2210.11518](https://arxiv.org/abs/2210.11518)  
**Date:** 2022-10-20  
**Summary page:** https://www.summarizepaper.com/en/paper/2210.11518v1/

## Key points

- Magnetars are a subset of isolated neutron stars that emit X-ray and radio waves due to the decay of their magnetic fields.
- A recent study detected a significant spin-down glitch event from the magnetar SGR~1935+2154 on October 5th, 2020.
- The glitch did not result in any changes to the source's persistent surface thermal or magnetospheric X-ray behavior nor evidence of strong X-ray bursting activity.
- Following the spin-down glitch event, SGR~1935+2154 emitted three FRB-like radio bursts followed by a month-long episode of pulsed radio emission.
- The synchronicity between these events suggests an association between them that could provide pivotal clues to their origin and triggering mechanisms with ramifications for broader magnetar and FRB populations.
- Impulsive crustal plasma shedding close to the magnetic pole generates a wind that combs out magnetic field lines rapidly reducing the star's angular momentum while temporarily altering its magnetospheric field geometry to permit pair creation needed for precipitating radio emission.
- This study sheds light on powerful winds generated by impulsive crustal plasma shedding near magnetic poles that can lead to FRB-like bursts and pulsed radio emission in magnetars.

## Summary

Magnetars are a unique subset of isolated neutron stars that emit X-ray and radio waves primarily due to the decay of their massive magnetic fields. In a recent study, researchers unveiled the detection of a large spin-down glitch event from the magnetar SGR~1935+2154 on October 5th, 2020. The glitch was significant with $|\Delta\nu/\nu| = 5.8_{-1.6}^{+2.6}\times10^{-6}$ but did not result in any changes to the source's persistent surface thermal or magnetospheric X-ray behavior nor evidence of strong X-ray bursting activity. However, in the days following the spin-down glitch event, SGR~1935+2154 emitted three FRB-like radio bursts followed by a month-long episode of pulsed radio emission. Given the rarity of both spin-down glitches and radio signals from magnetars, their approximate synchronicity suggests an association between these events that could provide pivotal clues to their origin and triggering mechanisms with ramifications for broader magnetar and FRB populations. The researchers postulate that impulsive crustal plasma shedding close to the magnetic pole generates a wind that combs out magnetic field lines rapidly reducing the star's angular momentum while temporarily altering its magnetospheric field geometry to permit pair creation needed for precipitating radio emission. This study sheds light on powerful winds generated by impulsive crustal plasma shedding near magnetic poles that can lead to FRB-like bursts and pulsed radio emission in magnetars. These findings have important implications for our understanding of these enigmatic objects and could help us unravel some of their mysteries.