Temperatures and Electron Densities in Flares as Derived from Spectroscopic Data

Abstract

It is shown that model flares with electron concentrations and temperatures in the ranges $$5\,\times\,{10}^{11}-{10}^{13}\,\text{cm}^{-3}\,\text{and}\,{10}^{4}-1.5\,\times\,{10}^{4}\,\text{deg}$$ . K respectively have emissions consistent with the observed hydrogen and helium line intensities in solar flare spectra. Some difficulties are shown to exist in interpreting the observed great line width of Hα and a possible solution is given.