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Updated: Jul 13, 2026
08:01
The Diffusion of Passive Tracers in Laminar Shear Flow
Published on: May 1, 2018
Diffusive radiation in one-dimensional Langmuir turbulence
1A.F. Ioffe Physico-Technical Institute, Russian Academy of Sciences, 194021 St. Petersburg, Russia.
Summary
Radiation spectra from relativistic particles interacting with Langmuir turbulence depend on particle motion angle. Oblique propagation creates complex spectra with power-law regions and high-frequency peaks, relevant for plasma physics and astrophysics.
Area of Science:
- Plasma Physics
- Astrophysical Radiation Mechanisms
- High-Energy Particle Dynamics
Background:
- Langmuir turbulence is a key plasma phenomenon, often generated by streaming instabilities.
- Understanding radiation from relativistic particles in turbulent plasmas is crucial for astrophysical and laboratory settings.
Purpose of the Study:
- To calculate and analyze radiation spectra produced by relativistic particles in one-dimensional Langmuir turbulence.
- To investigate the influence of particle velocity and electric field orientation on radiation characteristics.
Main Methods:
- Numerical calculations of radiation spectra.
- Analysis of particle motion in relation to electric field direction within turbulent plasma.
Main Results:
- Radiation spectra are highly sensitive to the angle between particle velocity and electric field.
- Transverse particle motion yields a degenerate spectrum, similar to uniform Langmuir oscillations.
- Oblique propagation results in complex spectra with multiple power-law regions and a potential high-frequency peak.
Conclusions:
- The orientation of particle motion significantly alters radiation spectra in turbulent plasmas.
- The findings are applicable to laboratory plasma experiments and astrophysical phenomena like gamma-ray bursts and jets.
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