Damped transverse oscillations of interacting coronal loops

TL;DR

This paper presents a semi-analytic T-matrix method to study resonantly damped transverse oscillations in interacting coronal loops, revealing how loop interactions influence oscillation properties in the solar corona.

Contribution

It introduces a novel semi-analytic approach using T-matrix theory to analyze collective oscillations of multiple interacting coronal loops, including damping effects.

Findings

Interaction modifies oscillation frequencies and damping rates.

The method applies to arbitrary configurations of loops.

Results include specific cases of two interacting loops.

Abstract

Damped transverse oscillations of magnetic loops are routinely observed in the solar corona. This phenomenon is interpreted as standing kink magnetohydrodynamic waves, which are damped by resonant absorption owing to plasma inhomogeneity across the magnetic field. The periods and damping times of these oscillations can be used to probe the physical conditions of the coronal medium. Some observations suggest that interaction between neighboring oscillating loops in an active region may be important and can modify the properties of the oscillations compared to those of an isolated loop. Here we theoretically investigate resonantly damped transverse oscillations of interacting non-uniform coronal loops. We provide a semi-analytic method, based on the T-matrix theory of scattering, to compute the frequencies and damping rates of collective oscillations of an arbitrary configuration of parallel cylindrical loops. The effect of resonant damping is included in the T-matrix scheme in the thin boundary approximation. Analytic and numerical results in the specific case of two interacting loops are given as an application.