Community of European Solar Radio Astronomers

Observation and Modeling of Small Spatial Structures of Solar Radio Noise Storms using the uGMRT by S. Mondal et al.

2025-09-02

One of the most commonly observed solar radio sources in the metric and decametric wavelengths are the so-called solar noise storms. These are generally associated with active regions and are believed to be powered by the plasma emission mechanism. Since plasma emission emits primarily at the fundamental and the harmonic of the local plasma frequency, the apparent angular size of the source can become significantly scatter-broadened due to the multi-path […]

A novel fine spectral structure of solar radio bursts with periodic beaded stripes observed by CBSm of CMP-II by Li et al.

2025-08-19

Substantial fine structures, such as zebras, drifting bursts, spikes, and fibers have been reported during the past decades of observations of solar radio bursts. These fine structures are frequently associated with the wide-band continuum such as type-IV bursts, at both metric and decametric wavelengths. They carry important information about the radiation process and coronal conditions. Previous studies have reported the so-called narrow-band stripes (e.g., Chernov 2008), characterized by a group […]

Polarization Analysis of Type III Langmuir/Z-mode Waves with Coherent Magnetic Component Observations by Solar Orbiter by T. Formánek et al.

2025-08-05

Type III solar radio bursts are generated by beams of energetic electrons propagating through interplanetary space. These electron beams, released from the Sun, travel along the Parker spiral and grow Langmuir waves through a kinetic instability in the electron velocity distribution function. The generated Langmuir waves subsequently undergo mode conversion, producing a radio emission at the plasma frequency or its harmonic. Langmuir waves are electrostatic waves generating the electric field […]

High School Students Nationwide Help Monitor Solar Activities with Radio Antennas by M. Akhavan-Tafti et al.

2025-07-23

It may surprise you to learn that when the Sun has an outburst, such as a solar flare or a giant eruption of charged gas called a coronal mass ejection (CME), it threatens the health and safety of astronauts or satellites in space. These events also send out invisible shock waves that can disrupt power grids and communications here on Earth. These shock waves produce special radio signals that can […]

Connecting energetic electrons at the Sun and in the heliosphere through X-ray and radio diagnostics by D. Paipa-Leon et al.

2025-06-10

Solar flares accelerate energetic electrons. While some of them escape into interplanetary space and produce interplanetary Type III solar radio bursts, the electrons interacting with the solar atmosphere produce Hard X-ray emission (HXR). Many studies relating the observations of type III radio bursts and HXR emissions have been performed since the first observations of their temporal association (e.g., Kane 1972, 1981). More recently, statistical studies were done by https://www.aanda.org/articles/aa/full_html/2025/02/aa52278-24/aa52278-24.html and James & Vilmer (2023) […]

Synchrotron or not – analysis of two-part type II bursts by Silja Pohjolainen

2025-05-27

A distinct class of interplanetary (IP) type II bursts that show single-lane, wide-band diffuse emission has been identified, but how these bursts are formed is still unclear. The radio burst on June 17-18, 2003 was analysed by Bastian (2007) , who suggested that the wide-band and diffuse part of the burst (type II-S in Fig. 1) could be due to synchrotron emission. The later part of the burst (type II-P) […]

ALMA Observations of Solar Spicules in a Coronal Hole by T. S. Bastian et al.

2025-05-13

Solar spicules were discovered by the Jesuit priest Angelo Secchi in 1877. They are small plasma jets of a few hundred kilometers in diameter that are launched to heights >10 Mm with speeds ranging from a few 10s of km/s to >100 km/s. Individually they have lifetimes of a few minutes. They occur in the chromospheric network over the entirety of the Sun. Early estimates (Beckers 1972) suggested that spicules […]

Multi-spacecraft Radio Observations Trace the Heliospheric Magnetic Field by D. L. Clarkson et al.

2025-04-25

Solar flares accelerate energetic electrons that escape into interplanetary space, guided by the Parker spiral magnetic field, and are responsible for the generation of the interplanetary Type III solar radio bursts. With multiple spacecraft now in orbit around the Sun (see e.g. Musset et al 2021), we are in a unique position of observing the propagation of radio emission through the heliosphere from multiple vantage points. Recent study by Clarkson […]