Spectroscopic Imaging of the Sun with MeerKAT: Opening a New Frontier in Solar Physics

TL;DR

This paper presents the first spectroscopic images of the Sun using MeerKAT, demonstrating high-fidelity imaging capabilities across a broad frequency range and opening new avenues for solar physics research.

Contribution

It provides the first spectroscopic images of the Sun with MeerKAT, validating their quality and exploring flux recovery at various frequencies, thus paving the way for advanced solar studies.

Findings

MeerKAT can recover nearly all flux at frequencies below 900 MHz.

High morphological similarity between observed and simulated images.

Potential to correct for missing flux at higher frequencies.

Abstract

Solar radio emissions provide several unique diagnostics to estimate different physical parameters of the solar corona, which are otherwise simply inaccessible. However, imaging the highly dynamic solar coronal emissions spanning a large range of angular scales at radio wavelengths is extremely challenging. At GHz frequencies, MeerKAT radio telescope is possibly globally the best-suited instrument at present for providing high-fidelity spectroscopic snapshot solar images. Here, we present the first published spectroscopic images of the Sun made using the observations with MeerKAT in the 880-1670 MHz band. This work demonstrates the high fidelity of spectroscopic snapshot MeerKAT solar images through a comparison with simulated radio images at MeerKAT frequencies. The observed images show extremely good morphological similarities with the simulated images. Our analysis shows that below ~900 MHz MeerKAT images can recover essentially the entire flux density from the large angular scale solar disc. Not surprisingly, at higher frequencies, the missing flux density can be as large as ~50%. However, it can potentially be estimated and corrected for. We believe once solar observation with MeerKAT is commissioned, it will enable a host of novel studies, open the door to a large unexplored phase space with significant discovery potential, and also pave the way for solar science with the upcoming Square Kilometre Array-Mid telescope, for which MeerKAT is a precursor.