A QED Model for the Origin of Bursts from SGRs and AXPs

Abstract

We propose a model to account for the bursts from soft gamma repeaters (SGRs) and anomalous X-ray pulsars (AXPs) in which quantum electrodynamics (QED) plays a vital role. In our theory, that we term ``fast-mode breakdown,'' magnetohydrodynamic (MHD) waves that are generated near the surface of a neutron star and propagate outward through the magnetosphere will be modified by the polarization of the vacuum. For neutron star magnetic fields $B_\rmscr{NS} \gtrsim B_\rmscr{QED} \approx 4.4 \times 10^{13}$ G, the interaction of the wave fields with the vacuum produces non-linearities in fast MHD waves that can steepen in a manner akin to the growth of hydrodynamic shocks. Under certain conditions, fast modes can develop field discontinuities on scales comparable to an electron Compton wavelength, at which point the wave energy will be dissipated through electron-positron pair production. We show that this process operates if the magnetic field of the neutron star is sufficiently strong and the ratio of the wavelength of the fast mode to its amplitude is sufficiently small, in which case the wave energy will be efficiently converted into an extended pair-plasma fireball. The radiative output from this fireball will consist of hard X-rays and soft $\gamma$-rays, with a spectrum similar to those seen in bursts from SGRs and AXPs (abridged).

28 pages, 5 figures, accepted by ApJ, minor changes to reflect accepted version

References in corpus (13)

• A Major SGR-like Outburst and Rotation Glitch in the No-Longer-So-Anomalous X-ray Pulsar 1E 2259+586
• Magnetar-like X-ray Bursts from an Anomalous X-ray Pulsar
• Changes in the X-ray Emission from the Magnetar Candidate 1E 2259+586 during its 2002 Outburst
• Discovery of Cyclotron Resonance Features in the Soft Gamma Repeater SGR 1806-20
• PSR J1847-0130: A Radio Pulsar with Magnetar Spin Characteristics
• New Evidence for Proton Cyclotron Resonance in a Magnetar Strength Field from SGR 1806-20
• Unraveling the cooling trend of the Soft Gamma Repeater, SGR 1627-41
• The detection of variability from the candidate IR counterpart to the Anomalous X-ray Pulsar 1E1048.1-5937
• The IR counterpart to the Anomalouos X-ray Pulsar 1RXS J1708-4009
• Can Thin Disks Produce Anomalous X-Ray Pulsars?
• The Likely Near-Infrared Counterpart to the Anomalous X-Ray Pulsar 1E 1048.1-5937
• On the Infrared, Optical and High Energy Emission from the Anomalous X-Ray Pulsar 4U 0142+615
• On the Enhanced X-ray Emission from SGR 1900+14 after the August 27 Giant Flare

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• Soft and Hard X-Ray Emissions from the Anomalous X-ray Pulsar 4U 0142+61 Observed with Suzaku
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• NuSTAR Observations of Magnetar 1E 1048.1-5937
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• X-ray emission from magnetic dissipation in the magnetar magnetosphere