Recent identification of the line from helium-like ions in the solar soft X-ray spectrum, followed by calculation of its transition probability, enables an analysis of the observations to be carried out, based on intensities of the three lines zZP-^AS, and z^S-^AS. The relative collision rates to the excited levels and the electron densities in the emitting regions have been determined, subject to the limitation of available observations. Densities of 3 x 10 8 cm-3 are found from lines formed over the quiet corona, but values of between 10 9 and 10 11 cm" 3 are found from lines emitted in active regions, and the highest electron densities occur in the hottest regions.

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