Combined Modeling of Acceleration, Transport, and Hydrodynamic Response in Solar Flares: I. The Numerical Model

Abstract

Acceleration and transport of high-energy particles and fluid dynamics of atmospheric plasma are interrelated aspects of solar flares. We present here self-consistently combined Fokker-Planck modeling of particles and hydrodynamic simulation of flare plasma. Energetic electrons are modeled with the Stanford unified code of acceleration, transport, and radiation, while plasma is modeled with the NRL flux tube code. We calculated the collisional heating rate from the particle transport code, which is more accurate than those based on approximate analytical solutions. We used a realistic spectrum of injected electrons provided by the stochastic acceleration model, which has a smooth transition from a quasi-thermal background at low energies to a nonthermal tail at high energies. The inclusion of low-energy electrons results in relatively more heating in the corona (vs. chromosphere), a larger downward conductive flux, and thus a stronger chromospheric evaporation than obtained in previous studies, which had a deficit in low-energy electrons due to an arbitrarily assumed low-energy cutoff. The energy and spatial distributions of energetic electrons and bremsstrahlung photons bear signatures of the changing density distribution caused by chromospheric evaporation. In particular, the density jump at the evaporation front gives rise to enhanced X-ray emission.

Accepted by ApJ (2009 June 12), 15 page, 12 figures

References in corpus (6)

• Double Coronal Hard and Soft X-ray Source Observed by RHESSI: Evidence for Magnetic Reconnection and Particle Acceleration in Solar Flares
• RHESSI Observation of Chromospheric Evaporation
• Particle acceleration mechanisms
• Stereoscopic electron spectroscopy of solar hard X-ray flares with a single spacecraft
• Hard X-ray Spectra and Positions of Solar Flares observed by RHESSI: photospheric albedo, directivity and electron spectra
• A Hot Microflare Observed With RHESSI and Hinode

Cited by in corpus (15)

• Evidence of Non-Thermal Particles in Coronal Loops Heated Impulsively by Nanoflares
• Imaging and spectroscopic observations of magnetic reconnection and chromospheric evaporation in a solar flare
• The Atmospheric Response to High Nonthermal Electron Beam Fluxes in Solar Flares I: Modeling the Brightest NUV Footpoints in the X1 Solar Flare of 2014 March 29
• Detection of Flare-induced Plasma Flows in the Corona of EV Lac with X-ray Spectroscopy
• Properties of chromospheric evaporation and plasma dynamics of a solar flare from IRIS observations
• Evidence of Explosive Evaporation in a Microflare Observed by Hinode/EIS
• The F-CHROMA grid of 1D RADYN flare models
• The Atmospheric Response to High Nonthermal Electron Beam Fluxes in Solar Flares. II. Hydrogen Broadening Predictions for Solar Flare Observations with the Daniel K. Inouye Solar Telescope
• Modeling the thermal conduction in the solar atmosphere with the code MANCHA3D
• Plasma heating in solar flares and their soft and hard X-ray emissions
• Time variations of observed H$\alpha$ line profiles and precipitation depths of non-thermal electrons in a solar flare
• Perspectives of current-layer diagnostics in solar flares
• Energy Diffusion and Advection Coefficients in Kinetic Simulations of Relativistic Plasma Turbulence
• Onset of Electron Acceleration in a Flare Loop
• Stochastic Acceleration of Electrons by Fast Magnetosonic Waves in Solar Flares: the Effects of Anisotropy in Velocity andWavenumber Space