# Solar type III bursts with high-frequency cut-off

## TL;DR

This paper reports on solar type III radio bursts with a high-frequency cut-off observed by UTR-2, linking the cut-off to propagation effects behind the solar limb and analyzing their characteristics.

## Contribution

It introduces the observation of high-frequency cut-offs in solar type III bursts and analyzes their properties and possible propagation origins.

## Key findings

- Cut-off frequencies vary between 30-55 MHz.
- Bursts are associated with solar activity behind the solar limb.
- Propagation effects influence the observed high-frequency cut-off.

## Abstract

New results in the study of solar type III bursts observed with the UTR-2 radio telescope are presented. The main feature of these bursts is a high-frequency cut-off. The solar activity manifestation was connected with the emergency of a new group of solar spots behind the solar limb relative to an observer on the Earth. This burst type was identified by analyzing its frequency drift rate, duration and flux depending on frequency. The solar bursts were linked to a group of similar events. The cut-off frequency is different from burst to burst and lies within 30-55 MHz. The cut-off origin is considered in the context of propagation effects between the burst sources moving behind the solar limb and the ground-based radio instruments.