Statistical and Temporal Analysis of Multi-component Burst-clusters from the Repeating FRB 20190520B

TL;DR

This study analyzes the morphology and spectral properties of multi-component bursts from FRB 20190520B and other active FRBs, revealing scale-free behavior and no periodicity, which sheds light on their emission mechanisms.

Contribution

It provides a systematic comparison of multi-component burst structures across multiple FRBs and identifies scale-free distributions indicative of SOC processes.

Findings

Multi-component bursts have spectral properties similar to single-peak bursts.

No periodicity detected in the temporal behavior of burst components.

Component-count distributions follow a power law, indicating scale-free behavior.

Abstract

Fast Radio Bursts (FRBs) are bright, millisecond-duration extragalactic radio transients that probe extreme astrophysical environments. Many FRBs exhibit multi-component structures, which encode information about their emission mechanisms or progenitor systems and thus provide important clues to their origins. In this work, we systematically analyze the burst morphology of FRB 20190520B and compare component distributions across four active FRBs observed with FAST: FRB 20121102A, FRB 20190520B, FRB 20201124A, and FRB 20240114A. We find that multi-component burst-clusters show spectral properties similar to single-peak bursts, and no periodicity is detected in their temporal behavior. The component-count distributions follow a power law, revealing scale-free behavior consistent with self-organized criticality (SOC) processes. Multi-component clusters account for 12-30% of all detected bursts, regardless of source activity, providing new insights into burst-to-burst variability and the physical processes driving FRB emission.