On the Transport and Acceleration of Solar Flare Particles in a Coronal Loop
Abstract
The turbulent environment of a flaring solar coronal loop directly affects the population of particles to be accelerated or already accelerated. Under the assumption of a uniform turbulent MHD wave field within the loop, the behavior of a particle distribution as it interacts with the turbulence is discussed, including particle precipitation to the footpoints of the loop and the evolution of the energy distribution as the particles undergo second-order stochastic acceleration. Two cases are discussed in detail: (1) particles spatially diffusing within the loop and precipitating with minimal acceleration in the short time scale of an impulsive event and (2) particles diffusing in both real and momentum space in a long duration event. Collisional losses due to ambient electrons are included. The gamma-ray flare of June 3, 1982 is modeled, and good agreement is obtained between predicted and observed time profiles if the loop length is 100,000 km with an intrinsic spatial diffusion time of 100-450 s. It follows that the production of high-energy neutrons and pi mesons extends over a time scale of 1000 s as observed.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- February 1991
- DOI:
- 10.1086/169695
- Bibcode:
- 1991ApJ...368..316R
- Keywords:
-
- Coronal Loops;
- Particle Acceleration;
- Solar Flares;
- Transport Theory;
- Astronomical Models;
- Energy Distribution;
- Gamma Ray Bursts;
- Magnetohydrodynamic Waves;
- Particle Collisions;
- Solar X-Rays;
- Solar Physics;
- GAMMA RAYS: BURSTS;
- PARTICLE ACCELERATION;
- SUN: CORONA;
- SUN: FLARES;
- SUN: X-RAYS;
- TURBULENCE