Stochastic coupling of solar photosphere and corona

TL;DR

This paper investigates the coupling between the solar photosphere and corona, revealing that multiscale intermittent dissipation in the corona is driven by turbulent photospheric convection and is characterized by complex, nonlocal magnetic interactions.

Contribution

It introduces an ensemble-based approach to analyze photosphere-corona coupling, deriving scaling relations that link photospheric observations to coronal dynamics.

Findings

Photospheric and coronal energy release events follow similar probability distributions.

Coronal dissipation at scales > 3 Mm is controlled by turbulent convection.

Coupling is nonlocal and non-deterministic due to complex magnetic topology.

Abstract

The observed solar activity is believed to be driven by the dissipation of nonpotential magnetic energy injected into the corona by dynamic processes in the photosphere. The enormous range of scales involved in the interaction makes it difficult to track down the photospheric origin of each coronal dissipation event, especially in the presence of complex magnetic topologies. In this paper, we propose an ensemble-based approach for testing the photosphere - corona coupling in a quiet solar region as represented by intermittent activity in SOHO MDI and STEREO EUVI image sets. For properly adjusted detection thresholds corresponding to the same degree of intermittency in the photosphere and corona, the dynamics of the two solar regions is described by the same occurrence probability distributions of energy release events but significantly different geometric properties. We derive a set of scaling relations reconciling the two groups of results and enabling statistical description of coronal dynamics based on photospheric observations. Our analysis suggests that multiscale intermittent dissipation in the corona at spatial scales > 3 Mm is controlled by turbulent photospheric convection. Complex topology of the photospheric network makes this coupling essentially nonlocal and non-deterministic. Our results are in an agreement with the Parker's coupling scenario in which random photospheric shuffling generates marginally stable magnetic discontinuities at the coronal level, but they are also consistent with an impulsive wave heating involving multiscale Alfvenic wave packets and/or MHD turbulent cascade. A back reaction on the photosphere due to coronal magnetic reconfiguration can be a contributing factor.