Exploring the origin of solar energetic electrons. II. Investigating turbulent coronal acceleration

Correlation of spectral indices between remote and in situ energy spectra presents the possibility of a common source-acceleration region within the corona, however the properties and location of this region are not well constrained. To investigate this, we perform a parameter study for both the properties of the ambient plasma of a simulated acceleration region and the turbulent acceleration profile acting on an initially isotropic thermal electron population.

We find that independently varying the turbulent acceleration timescale τ acc , acceleration profile standard deviation σ , and acceleration region length L result in an in situ spectral index variation of between 0.5 and 2.0 at 1.0 au for <100 keV electrons. Short-timescale turbulent scattering in the flaring corona steepens the spectra by ~0.5. It was also found that the in situ spectral index δ derived from the peak electron flux produces a spectral index ~1.6 harder than that from a full-flare X-ray photon flux (of spectral index γ ) simulated with the same intermediate parameters.