Particle acceleration in solar flares with imaging-spectroscopy in soft X-rays

TL;DR

This paper emphasizes the importance of imaging-spectroscopy in soft X-rays combined with multi-wavelength observations and simulations to better understand particle acceleration mechanisms during solar flares, a key challenge in plasma physics.

Contribution

It advocates for the use of soft X-ray imaging-spectroscopy as a crucial tool to elucidate particle acceleration in solar flares, integrating observational and simulation approaches.

Findings

Imaging-spectroscopy in SXRs can reveal the context of particle acceleration.

Multi-wavelength observations are essential for comprehensive understanding.

Numerical simulations will help interpret observational data.

Abstract

Particles are accelerated to very high, non-thermal energies during explosive energy-release phenomena in space, solar, and astrophysical plasma environments. In the case of solar flares, it has been established that magnetic reconnection plays an important role for releasing the magnetic energy, but it remains unclear if or how magnetic reconnection can further explain particle acceleration during flares. Here we argue that the key issue is the lack of understanding of the precise context of particle acceleration but it can be overcome, in the near future, by performing imaging-spectroscopy in soft X-rays (SXRs). Such observations should be complemented by observations in other wavelengths such as extreme-ultraviolets (EUVs), microwaves, hard X-rays (HXRs), and gamma-rays. Also, numerical simulations will be crucial for further narrowing down the particle acceleration mechanism in the context revealed by the observations. Of all these efforts, imaging-spectroscopy in SXRs, if successfully applied to large limb flares, will be a milestone in our challenge of understanding electron acceleration in solar flares and beyond, i.e. the Plasma Universe.