Abstract
In the light of a recent discussion by Gerassimenko and Nolte (1978) we re-examine the use of the ‘filter ratio method’ for determining the thermodynamic parameters of coronal plasmas. We conclude that the method gives reliable results only when the observed plasma is nearly isothermal and that presently available data do not demonstrate that active region plasmas generally meet this condition.
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Underwood, J.H., McKenzie, D.L. Further remarks on the analysis and interpretation of solar X-ray photographs. Sol Phys 60, 311–314 (1978). https://doi.org/10.1007/BF00156531
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DOI: https://doi.org/10.1007/BF00156531