# Solar Energetic Particle Acceleration by a Shock Wave Accompanying a Coronal Mass Ejection in the Solar Atmosphere

## TL;DR

This study models how shock waves from coronal mass ejections accelerate solar energetic particles, showing that particle energies can reach up to 10 GeV and aligning well with observed data.

## Contribution

It provides a numerical framework for simulating particle acceleration during CMEs using realistic parameters and relates CME/shock dynamics to particle spectra.

## Key findings

- Maximum particle energies reach 0.1-10 GeV.
- CME radii of 3-5 solar radii match observations.
- Particle spectra align with ground-based detector data.

## Abstract

Solar energetic particles acceleration by a shock wave accompanying a coronal mass ejection (CME) is studied. The description of the accelerated particle spectrum evolution is based on the numerical calculation of the diffusive transport equation with a set of realistic parameters. The relation between the CME and the shock speeds, which depend on the initial CME radius, is determined. Depending on the initial CME radius, its speed, and the magnetic energy of the scattering Alfven waves, the accelerated particle spectrum is established during 10-60 minutes from the beginning of CME motion. The maximum energies of particles reach 0.1-10 GeV. The CME radii of 3-5 $R_\odot$ and the shock radii of 5-10 $R_\odot$ agree with observations. The calculated particle spectra agree with the observed ones in events registered by ground-based detectors if the turbulence spectrum in the solar corona significantly differs from the Kolmogorov one.