P19

Presentation Title: Maximum Attainable Energy of Particles in Solar Flares
Author(s): Mitsuo Oka

Abstract:

Particles are accelerated to very high, non-thermal energies in solar and space plasmas. While various mechanisms of particle acceleration have been proposed, it remains unclear what limits the maximum energy of particles in each plasma environment. Here we show the observed maximum energy of particles in solar and space plasmas roughly aligns with the energy predicted by the Hillas limit, a concept often invoked in astrophysics. However, this correlation depends on certain assumptions, and in some cases, the observed maximum energy exceeds or falls short of the predicted energy. We hope that this study serves as a starting point for more detailed discussions of a possible scaling law and offers a fresh perspective on particle acceleration in solar flares.