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Updated: Dec 15, 2025
11:20
Investigation of Early Plasma Evolution Induced by Ultrashort Laser Pulses
Published on: July 2, 2012
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Origin of Pulsar Radio Emission
Alexander Philippov1, Andrey Timokhin2, Anatoly Spitkovsky3
1Center for Computational Astrophysics, Flatiron Institute, 162 Fifth Avenue, New York, New York 10010, USA.
Physical Review Letters
|July 9, 2020
Summary
Pulsar radio emission may originate from nonstationary pair plasma discharges. In simulations, nonuniform plasma creation generates electromagnetic waves, explaining observed pulsar signals.
Area of Science:
- Plasma Physics
- Astrophysics
- Computational Physics
Background:
- The origin of coherent radio emission from pulsars remains a long-standing mystery in astrophysics.
- Pulsar magnetospheres are filled with plasma generated through pair creation processes.
Purpose of the Study:
- To investigate the generation mechanism of coherent radio emission in pulsar magnetospheres.
- To determine if plasma discharges can directly produce observable electromagnetic waves.
Main Methods:
- Large-scale two-dimensional kinetic plasma simulations were employed.
- Simulations focused on nonstationary pair plasma discharges with nonuniform creation across magnetic field lines.
- Localized simulations analyzed the electric field screening process.
Main Results:
- Nonuniform pair creation during plasma discharges leads to the emission of electromagnetic waves.
- These waves were identified as superluminal ordinary (O) modes.
- The simulated wave spectrum is broadband and matches the frequency range of observed pulsar radio emission.
Conclusions:
- Nonstationary pair plasma discharges are a viable source of coherent radio emission in pulsars.
- The escape of O-mode waves from the magnetosphere is facilitated by decreasing plasma density.
- This finding offers a potential explanation for the observed characteristics of pulsar radio emission.
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