fluctuations

Tracing Ion-Scale Turbulence and Energy Cascade Rate from the Solar Corona to 1 au by E. P. Kontar et al.

January 20, 2026

The solar corona and solar wind are turbulent plasma environments where energy transfer from large-scale magnetohydrodynamic (MHD) fluctuations to smaller kinetic scales is thought to play a critical role in coronal heating and solar wind acceleration. Despite decades of research, the properties of turbulence at ion scales, where dissipation occurs, remain poorly constrained due to limited observational data. Moreover, the precise mechanisms that heat the corona, and accelerate and heat […]

Temporally resolved Type III solar radio bursts in the frequency range 3-13 MHz by A. Vecchio et al.

December 17, 2024

Type III radio bursts are the most common coherent radio emission produced by the Sun. They are characterized by a rapid drift in time towards lower frequencies and represent an indirect signature of energetic electrons produced at the Sun during a flare and propagating through the plasma of the corona and the interplanetary medium. Type III bursts are observed over a wide range of frequencies ranging from about ∼500 MHz […]

The angular and frequency dependence of solar radio burst rise and decay times using multi-spacecraft observations by Nicolina Chrysaphi et al.

August 27, 2024

Density fluctuations populating the heliosphere interfere with propagating radio photons, altering their trajectories through frequency-dependent effects like scattering. Crucially, these density fluctuations are anisotropic, leading to anisotropic scattering and directional radio-wave propagation. This means that observers at different positions may obtain different estimations of radio properties. Such effects are particularly evident in solar radio bursts which are emitted through the plasma emission mechanism. It has been shown that detectors at […]

Energetics of compressive waves in the solar corona by Francesco Azzollini et al

July 2, 2024

Inelastic scattering off moving or oscillating density fluctuations leads to broadening of radio signals propagating in the solar corona and solar wind. Using an anisotropic density fluctuation model from the kinetic scattering theory for solar radio bursts, we deduce the plasma velocities (perpendicular to the line of sight) required to explain observations of spacecraft signal frequency broadening. The kinetic energy associated with these inferred bulk velocities cascades to smaller and […]

web page images

An Interactive Visual Tool for the Anisotropic Scattering of Solar Radio Bursts by Daniel L. Clarkson et al

February 6, 2024

The turbulent heliosphere has a significant effect on the observed characteristics of radio emission produced in, or viewed through, the solar atmosphere. In particular, radio-wave scattering on density irregularities can broaden the observed decay times and source sizes, and shift the apparent source position. Both radio burst observations and simulations have demonstrated that the turbulence is anisotropic, which can explain both the observed decay times and source sizes simultaneously. Considering […]