plasma radio emission

MeerKAT imaging spectroscopy reveals multiple electron acceleration sites in a solar flare by Luo et al.

June 9, 2026

Solar flares are the most explosive energy-release events in the solar corona, leading to intense particle acceleration, plasma heating, and bulk plasma motions on short timescales. Core questions during solar flares remain unresolved, including how and where particle acceleration occurs, and how energized electrons propagate through coronal magnetic structures. Radio observations, due to their unique sensitivity to nonthermal and thermal electrons, serve as powerful diagnostics of electron dynamics and high-temperature […]

Anisotropic density turbulence variation from the low corona to 1 au as deduced from solar radio observations by E. Kontar et al.

November 30, 2023

Density turbulence in the solar corona and solar wind is evident via the properties of solar radio bursts; angular scattering-broadening of extra-solar radio sources observed through the solar atmosphere, and can be measured in-situ in the solar wind. A viable density turbulence model should simultaneously explain all three types of density fluctuation observations. Solar radio bursts (e.g. Type I, II, III) observed below ~1 GHz are produced predominantly via plasma […]

Third and fourth harmonics of electromagnetic emissions by a weak beam in a solar wind plasma with random density fluctuations by C. Krafft

November 22, 2022

Electromagnetic emissions at the third harmonic of the plasma frequency $\omega _{p}$ have been reported during the occurrence of type II and type III solar radio bursts (e.g. Zlotnik 1978, Zlotnik et al. 1998, Cairns; 1986), even if rarely and sometimes controversially. Recently the Wind spacecraft detected several events exhibiting third harmonic emissions in interplanetary type III bursts observed locally near 1 AU (Reiner and MacDowald; 2019). For the first […]

Fundamental electromagnetic emissions by a weak electron beam in solar wind plasmas with density fluctuations by C. Krafft and P. Savoini

April 5, 2022

Solar radio bursts of Type III were currently observed since decades in the interplanetary space (Reid and Ratcliffe, 2014). They result from a series of successive processes arising in solar coronal and wind plasmas where Langmuir wave turbulence is radiated by electron beams generated during flares, leading ultimately to the emission of electromagnetic waves at the fundamental plasma frequency $\omega _{p}$ and its second harmonic. The Letter by Krafft and […]

Particle-in-cell simulation of plasma emission in solar radio bursts by T. M. Li et al.

December 21, 2021

Solar radio radiation is one of the most sensitive emissions during solar eruptions, where type III radio bursts can provide clues for electron acceleration and propagation. Type III radio bursts are widely accepted to result from the plasma emission, which is observationally supported by the presence of Langmuir waves, and excited electromagnetic waves at fundamental and harmonic frequencies from the nonlinear wave coupling (Ginzburg & Zhelezniakov 1958). Such a mechanism […]