Analysis and Modelling of a Type II White-light Solar Flare

A unique set of multi-instrument observations is presented with broad wavelength range spectra in the visible and UV range. Data from the RHESSI and Fermi satellites provide evidence of both non-thermal electron and proton beams during the studied flare.

The observations put important constraints on the beam parameters and allow a deeper investigation using radiative hydrodynamic modelling.<br> <br> Radiative hydrodynamic simulations show that the observed flare signatures cannot be<br>explained with ‘standard’ electron beams, since such beams deposit at least part of their energy in the upper chromosphere where hydrogen lines are formed. Instead, the models suggest that the beams penetrate through the upper chromosphere and deliver their energy directly into the lower chromosphere.