Millisecond solar radio bursts in the metric wavelength range

TL;DR

This paper investigates super-short structures in solar radio bursts, classifying them into various categories based on their duration and spectral properties, revealing their solar origin and diverse morphologies.

Contribution

It provides a detailed classification of millisecond solar radio bursts during metric type IV events, highlighting their properties and origins.

Findings

SSSs have durations of 4-50 ms, up to 10 times shorter than spikes.

Confirmed solar origin through spectral and high-resolution measurements.

Identified multiple morphological categories of SSSs, including broad-band, narrow-band, and complex types.

Abstract

A study and classification of super-short structures (SSSs) recorded during metric type IV bursts is presented. The most important property of SSSs is their duration, at half power ranging from 4-50 ms, what is up to 10 times shorter than spikes at corresponding frequencies. The solar origin of the SSSs is confirmed by one-to-one correspondence between spectral recordings of Artemis-IV1 and high time resolution single frequency measurements of the TSRS2. We have divided the SSSs in the following categories: 1. Broad-Band SSSs: They were partitioned in two subcategories, the SSS-Pulses and Drifting SSSs; 2. Narrow-band: They appear either as Spike-Like SSSs or as Patch-Like SSSs; 3. Complex SSS: They consist of the absorption-emission segments and were morphologically subdivided into Rain-drop Bursts (narrow-band emission head and a broad-band absorption tail) and Blinkers.