# Are chains of type I radio bursts generated by similar processes as drifting pulsation structures observed during solar flares?

## TL;DR

This paper compares chains of type I radio bursts and drifting pulsation structures (DPSs), proposing a unified model based on magnetic reconnection and plasmoid interactions, and explores their differences and diagnostic potential for magnetic field estimation.

## Contribution

It introduces a new model linking chains of type I bursts to DPSs through magnetic reconnection and plasmoid interactions, explaining their similarities and differences.

## Key findings

- Chains of type I bursts can be generated by magnetic reconnection involving plasmoids.
- Merging plasmoids affect the radio spectrum and can explain the 'wavy' appearance of some burst chains.
- Chains of type I bursts can be used to estimate magnetic field strength in their sources.

## Abstract

We present examples of the both types of bursts and show their similarities and differences. Then for chains of type I bursts a similar model as for drifting pulsation structures (DPSs) is proposed. We show that similarly as in the DPS, the chains of type I bursts can be generated by the fragmented magnetic reconnection associated with plasmoids interactions. To support this new model of chains of type I bursts, we present an effect of merging of two plasmoids to one larger plasmoid on the radio spectrum of DPS. This process can also explain the "wavy" appearance of some chains of type I bursts. Then we show that the chains of type I bursts with the "wavy" appearance can be used for estimation of the magnetic field strength in their sources. We think that differences of chains of type I bursts and DPSs are mainly owing to different regimes of the magnetic field reconnection. While in the case of chains of type I bursts the magnetic reconnection and plasmoid interactions are in the quasi-separatrix layer of the active region in more or less quasi-saturated regime, in the case of DPSs, observed in the impulsive phase of eruptive flares, the magnetic reconnection and plasmoids interactions are in the current sheet formed under the flare magnetic rope, which moves upwards and forces this magnetic reconnection.