The Effects of Including Non-Thermal Particles in Flare Loop Models

TL;DR

This study uses the HyLoop model to investigate how non-thermal particles influence soft X-ray emissions in solar flare loops, revealing effects of acceleration location, loop geometry, and multi-loop interactions on observed emissions.

Contribution

It introduces a comprehensive simulation of flare emissions incorporating non-thermal particles with different acceleration sites and geometries, advancing understanding of flare dynamics and emissions.

Findings

Footpoint injection causes early peaks in emission ratios.

Non-thermal particles increase brightness in loop footpoints.

Cusp-shaped geometry results in smaller GOES flare class.

Abstract

In this work, we use HyLoop (Winter et al. 2011), a loop model that can incorporate the effects of both MHD and non-thermal particle populations, to simulate soft X-ray emissions in various situations. First of all, we test the effect of acceleration location on the emission in several XRT filters by simulating a series of post flare loops with different injection points for the non-thermal particle beams. We use an injection distribution peaked at the loop apex to represent a direct acceleration model, and an injection distribution peaked at the footpoints to represent the Alf\'en wave interaction model. We find that footpoint injection leads to several early peaks in the apex-tofootpoint emission ratio. Second, we model a loop with cusp-shaped geometry based on the eruptionmodel developed by Lin & Forbes (2000) and Reeves& Forbes (2005a), and find that early in the flare, emission in the loop footpoints is much brighter in the XRT filters if non-thermal particles are included in the calculation. Finally, we employ a multi-loop flare model to simulate thermal emission and compare with a previous model where a semi-circular geometry was used (Reeves et al. 2007). We compare the Geostationary Operational Environmental Satellite (GOES) emission from the two models and find that the cusp-shaped geometry leads to a smaller GOES class flare.