Closed-Field Coronal Heating Driven by Wave Turbulence

TL;DR

This paper develops a wave-turbulence-driven model for coronal heating that accounts for wave propagation, reflection, and dissipation, providing a physically motivated alternative to empirical models and applicable across various solar conditions.

Contribution

The study introduces a physically based WTD heating model for coronal loops that reduces free parameters and captures diverse solar phenomena more accurately.

Findings

WTD model reduces free parameters compared to empirical models.

The model explains short heating scale heights and thermal cycles.

Applicable to a broad range of quiet-sun and active regions.

Abstract

To simulate the energy balance of coronal plasmas on macroscopic scales, we often require the specification of the coronal heating mechanism in some functional form. To go beyond empirical formulations and to build a more physically motivated heating function, we investigate the wave-turbulence-driven (WTD) phenomenology for the heating of closed coronal loops. Our implementation is designed to capture the large-scale propagation, reflection, and dissipation of wave turbulence along a loop. The parameter space of this model is explored by solving the coupled WTD and hydrodynamic evolution in 1D for an idealized loop. The relevance to a range of solar conditions is also established by computing solutions for over one hundred loops extracted from a realistic 3D coronal field. Due to the implicit dependence of the WTD heating model on loop geometry and plasma properties along the loop and at the footpoints, we find that this model can significantly reduce the number of free parameters when compared to traditional empirical heating models, and still robustly describe a broad range of quiet-sun and active region conditions. The importance of the self-reflection term in producing relatively short heating scale heights and thermal nonequilibrium cycles is also discussed.