Interlinking internal and external magnetic fields of relativistically rotating neutron stars

Abstract

This work presents a global solution for the internal and the external field of an axisymmetric rotating neutron star. It is shown that the twist of the internal field affects the external field, by increasing the number of open field lines and eventually the spin-down rate of the star. This effect is far more drastic if the toroidal field, and consequently the poloidal current flowing within the star, is allowed to populate the closed field lines of the magnetosphere, rather than if it remains confined in the star. We further remark that the internal field structure depends on the presence of a twisted magnetosphere: if the twist current is not allowed to flow in the magnetosphere it only occupied a narrow toroid at the interior of the star, whereas if the twist currents are allowed to flow in the magnetosphere the internal toroidal field may occupy a significant volume of the stellar interior. Strong magnetospheric currents may also impact the emission mechanisms, and lead to fluctuations in magnetar spin-down rates, moding and nulling of pulsars, a correlation between angular shear and twist, and the general morphology of the pulsar magnetic field leading to various observational manifestations. The magnetospheric toroidal fields may possibly dissipate, thus the system may switch from global twist to internal twist and consequently exhibit transient behavior.

11 pages, 11 figures

References in corpus (26)

• Switched magnetospheric regulation of pulsar spin-down
• Corona of Magnetars
• Untwisting magnetospheres of neutron stars
• Modelling magnetically deformed neutron stars
• Electrodynamics of axisymmetric pulsar magnetosphere with electron-positron discharge: a numerical experiment
• Three-dimensional numerical simulations of the pulsar magentoshere: Preliminary results
• The magnetar 1E 1547.0-5408: radio spectrum, polarimetry, and timing
• Evidence for Heating of Neutron Stars by Magnetic Field Decay
• Plasmoid Instability in Forming Current Sheets
• General relativistic neutron stars with twisted magnetosphere
• Topology of magnetars external field. I. Axially symmetric fields
• A strong $\ddot{\nu }-\dot{\nu }$ correlation in radio pulsars with implications for torque variations
• Repeated, Delayed Torque Variations Following X-ray Flux Enhancements in the Magnetar 1E1048.1$-$5937
• On magnetic equilibria in barotropic stars
• Equilibrium solutions of relativistic rotating stars with mixed poloidal and toroidal magnetic fields
• Spin-down evolution and radio disappearance of the magnetar PSR J1622$-$4950
• Resistive Tearing Instability in Electron-MHD: Application to Neutron Star Crusts
• Two new outbursts and transient hard X-rays from 1E 1048.1$-$5937
• Fields from a relativistic magnetic explosion
• The 2022 high-energy outburst and radio disappearing act of the magnetar 1E 1547.0-5408
• Simultaneous magnetic polar cap heating during a flaring episode from the magnetar 1RXS J170849.0-400910
• Nonaxisymmetric Hall instability: A key to understanding magnetars
• The freedom to choose neutron star magnetic field equilibria
• Current closure through the neutron star crust
• Magnetic equilibria of relativistic axisymmetric stars: The impact of flow constants
• On the connection between radiative outbursts and timing irregularities in magnetars

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