A rotation-driven pulsar radio emission mechanism

Abstract

We propose and discuss an alternative pulsar radio emission mechanism that relies on rotation-driven plasma oscillations, rather than on a beam-driven instability, and suggest that it may be the generic radio emission mechanism for pulsars. We identify these oscillations as superluminal longitudinal waves in the pulsar plasma, and point out that these waves can escape directly in the O~mode. We argue that the frequency of the oscillations is ${\omega }_0\approx {\omega }_{\mathrm{p}}(2⟨\gamma ⟩{)}^{1/2}/{\gamma }_{\mathrm{s}}$, where ${\gamma }_{\mathrm{s}}$ is the Lorentz factor of bulk streaming motion and $⟨\gamma ⟩$ is the mean Lorentz factor in the rest frame of the plasma. The dependence of the plasma frequency ${\omega }_{\mathrm{p}}$ on radial distance implies a specific frequency-to-radius mapping, ${\omega }_0\propto r^{-3/2}$. Escape of the energy in these oscillations is possible if they are generated in overdense, field-aligned regions that we call fibers; the wave energy is initially refracted into underdense regions between the fibers, which act as ducts. Some implications of the model for the interpretation of pulsar radio emission are discussed.

Accepted for publication in MNRAS

References in corpus (7)

• Corona of Magnetars
• Time-dependent pair cascades in magnetospheres of neutron stars I. Dynamics of the polar cap cascade with no particle supply from the neutron star surface
• Variable VHE gamma-ray emission from non-blazar AGNs
• Polar-cap accelerator and radio emission from pulsars
• Multi-frequency integrated profiles of pulsars
• The Nature of Coherent Radio Emission from Pulsars
• Magnetar Corona

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• Radio Emission of Pulsars. II. Coherence Catalyzed by Cerenkov-Unstable Shear Alfvén Waves
• Bunch Expansion as a cause for Pulsar Radio Emissions
• Coherent emission from QED cascades in pulsar polar caps
• Radio polarization of millisecond pulsars with multipolar magnetic fields
• Antenna source of radio-frequency emission in ion-proton pulsars
• Externally-driven plasma models as candidates for pulsar radio emission
• Multifrequency evolution of the Integrated pulse profile of radio pulsars by implementing the inverse Compton mechanism
• Classification of Pulsars using Extreme Deconvolution