Modelling of Nonthermal Microwave Emission From Twisted Magnetic Loops

TL;DR

This paper models microwave gyrosynchrotron emission from nonthermal electrons in twisted magnetic loops, revealing how magnetic topology influences radio emission and polarization patterns, with implications for solar and stellar magnetic field diagnostics.

Contribution

It introduces a detailed simulation of gyrosynchrotron emission considering twisted magnetic fields and anisotropic electron distributions, highlighting the impact on polarization and source compactness.

Findings

Polarization sign inversion line is inclined to the loop axis.

Less twisted loops produce more compact radio sources.

Magnetic twist significantly affects polarization distribution.

Abstract

Microwave gyrosynchrotron radio emission generated by nonthermal electrons in twisted magnetic loops is modelled using the recently developed simulation tool GX Simulator. We consider isotropic and anisotropic pitch-angle distributions. The main scope of the work is to understand impact of the magnetic field twisted topology on resulted radio emission maps. We have found that nonthermal electrons inside twisted magnetic loops produce gyrosynchrotron radio emission with peculiar polarization distribution. The polarization sign inversion line is inclined relatively to the axis of the loop. Radio emission source is more compact in the case of less twisted loop, considering anisotropic pitch-angle distribution of nonthermal electrons.