Study of radio transients from the quiet Sun during an extremely quiet time

TL;DR

This study analyzes weak, impulsive, narrowband solar radio transients called WINQSEs during an extremely quiet solar period, confirming their ubiquity and impulsiveness, and highlighting differences from previous observations to deepen understanding.

Contribution

The paper presents an improved methodology for detecting WINQSEs during very quiet solar conditions, revealing their persistent presence and distinct properties compared to earlier studies.

Findings

WINQSEs are ubiquitously present on the quiet Sun.

Their impulsive and narrowband nature is confirmed.

Some properties differ significantly from previous observations.

Abstract

In this work we study a class of recently discovered metrewave solar transients referred to as Weak Impulsive Narrowband Quiet Sun Emission \citep[WINQSEs,][]{mondal2020}. Their strength is a few percent of the quiet Sun background and are characterised by their very impulsive, narrow-band and ubiquitous presence in quiet Sun regions. \citet{mondal2020} hypothesised that these emissions might be the radio counterparts of the nanoflares and their potential significance warrants detailed studies. Here we present an analysis of data from an extremely quiet time and with an improved methodology over the previous work. As before, we detect numerous WINQSEs, which we have used for their further characterisation. Their key properties, namely, their impulsive nature and ubiquitous presence on the quiet Sun are observed in these data as well. Interestingly, we also find some of the observed properties to differ significantly from the earlier work. With this demonstration of routine detection of WINQSEs, we hope to engender interest in the larger community to build a deeper understanding of WINQSEs.