Magnetar bursts due to Alfvén wave nonlinear breakout

Abstract

The most common form of magnetar activity is short X-ray bursts, with durations from milliseconds to seconds, and luminosities ranging from $10^{36}$ to $10^{43}\mathrm{erg}{\mathrm{s}}^{-1}$. Recently, an X-ray burst from the galactic magnetar SGR 1935+2154 was detected to be coincident with two fast radio burst (FRB) like events from the same source, providing evidence that FRBs may be linked to magnetar bursts. Using fully 3D force-free electrodynamics simulations, we show that such magnetar bursts may be produced by Alfvén waves launched from localized magnetar quakes: a wave packet propagates to the outer magnetosphere, becomes nonlinear, and escapes the magnetosphere, forming an ultra-relativistic ejecta. The ejecta pushes open the magnetospheric field lines, creating current sheets behind it. Magnetic reconnection can happen at these current sheets, leading to plasma energization and X-ray emission. The angular size of the ejecta can be compact, $\lesssim 1$ sr if the quake launching region is small, $\lesssim 0.01$ sr at the stellar surface. We discuss implications for the FRBs and the coincident X-ray burst from SGR 1935+2154.

14 pages, 11 figures, accepted for publication in ApJ

References in corpus (10)

• INTEGRAL discovery of a burst with associated radio emission from the magnetar SGR 1935+2154
• Particle acceleration in axisymmetric pulsar current sheets
• The synchrotron maser emission from relativistic shocks in Fast Radio Bursts: 1D PIC simulations of cold pair plasmas
• Pulsar Radio Emission Mechanism: Radio Nanoshots as a Low Frequency Afterglow of Relativistic Magnetic Reconnection
• Plasmoid ejection by Alfvén waves and the fast radio bursts from SGR 1935+2154
• Coherent Electromagnetic Emission from Relativistic Magnetized Shocks
• Electromagnetic fireworks: Fast radio bursts from rapid reconnection in the compressed magnetar wind
• Emission of magnetar bursts and precursors of neutron star mergers
• Black hole magnetosphere with small scale flux tubes--II. Stability and dynamics
• Magnetic loading of magnetars' flares

Cited by in corpus (19)

• Relativistic Magnetic Reconnection in Astrophysical Plasmas: A Powerful Mechanism of Nonthermal Emission
• Three-dimensional dynamics of strongly twisted magnetar magnetospheres: Kinking flux tubes and global eruptions
• Polarisation of magnetospheric curvature radiation in repeating fast radio bursts
• Fast radio bursts as precursor radio emission from monster shocks
• Relativistic coronal mass ejections from magnetars
• Direct Emission of Strong Radio Pulses During Magnetar Flares
• Narrow spectra of repeating fast radio bursts: A magnetospheric origin
• On the energy budget of starquake-induced repeating fast radio bursts
• An Intermediate-field Fast Radio Burst Model and the Quasi-periodic Oscillation
• Statistical Properties of X-Ray Bursts from SGR J1935+2154 Detected by Insight-HXMT
• Nonlinear Alfvén-wave Dynamics and Premerger Emission from Crustal Oscillations in Neutron Star Mergers
• Electrodynamics and dissipation in the binary magnetosphere of pre-merger neutron stars
• General relativistic force-free electrodynamics with a discontinuous Galerkin-finite difference hybrid method
• Relativistically Magnetized Collisionless Shocks in Pair Plasma: I. Solitons, Chaos, and Thermalization
• Magnetar Eruptions and Electromagnetic Fireworks
• Superluminal Wave Activation at Relativistic Magnetized Shocks
• Solitary Alfvén Waves
• Global Magnetohydrodynamic Simulations of Monster Shocks in Neutron Star Magnetospheres
• A Criterion for Magnetars Producing Giant Flares