Seismological constraints on the solar coronal heating function

TL;DR

This paper uses observations of slow magnetoacoustic waves to constrain the coronal heating function, addressing the balance of heating and cooling in the solar corona and its stability implications.

Contribution

It introduces a novel seismological approach to determine the coronal heating function by analyzing wave-induced stability in the solar corona.

Findings

Constraints on the coronal heating function derived from wave observations

Identification of conditions leading to thermal stability or instability in the corona

Insights into the energy balance mechanisms in the solar atmosphere

Abstract

The hot solar corona exists because of the balance between radiative and conductive cooling and some counteracting heating mechanism which remains one of the major puzzles in solar physics. The coronal thermal equilibrium is perturbed by magnetoacoustic waves which are abundantly present in the corona, causing a misbalance between the heating and cooling rates. Due to this misbalance, the wave experiences a back-reaction, either losing or gaining energy from the energy supply that heats the plasma, at the time scales comparable to the wave period. In particular, the plasma can be subject to wave-induced instability or over-stability, depending on the specific choice of the coronal heating function. In the unstable case, the coronal thermal equilibrium would be violently destroyed, which does not allow for the existence of long-lived plasma structures typical for the corona. Based on this, we constrained the coronal heating function using observations of slow magnetoacoustic waves in various coronal plasma structures.