A simple model for the evolution of multi-stranded coronal loops

TL;DR

This paper presents a cellular automaton model that simulates the evolution of coronal loops, reproducing observed properties and providing insights into their heating and decay processes.

Contribution

A simple CA model for coronal loop evolution based on magnetic stress relaxation and nanoflares, matching observed light curve characteristics.

Findings

Synthetic light curves resemble observed coronal loops

Model parameters follow scaling laws with observational predictions

Implications for understanding coronal heating mechanisms

Abstract

We develop and analyze a simple cellular automaton (CA) model that reproduces the main properties of the evolution of soft X-ray coronal loops. We are motivated by the observation that these loops evolve in three distinguishable phases that suggest the development, maintainance, and decay of a self-organized system. The model is based on the idea that loops are made of elemental strands that are heated by the relaxation of magnetic stress in the form of nanoflares. In this vision, usually called "the Parker conjecture" (Parker 1988), the origin of stress is the displacement of the strand footpoints due to photospheric convective motions. Modeling the response and evolution of the plasma we obtain synthetic light curves that have the same characteristic properties (intensity, fluctuations, and timescales) as the observed cases. We study the dependence of these properties on the model parameters and find scaling laws that can be used as observational predictions of the model. We discuss the implications of our results for the interpretation of recent loop observations in different wavelengths.