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Temperature variations of one well-known UV ceti type flare star

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Abstract

Temperature variations of the flare star, EV Lac, at its quiet-state luminosity were computed from its colour indices,B - V, which were measured in Johnson's system, these daily temperature changes are the essential reason of the short-term behaviour appearance in the flare star which is due to the presence of active region(s) causing a temperature difference of a few hundred degrees from the photosphere. A correlation between the annual mean of temperature variations of the flare star at its quiet-state and the annual rate of some physical parameters of the flare star at its active-state was detected. This correlation can interpret the occurrence of the long-term behaviour of the flare star at its quiescent-state as found by Mavridiset al. (1982).

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  1. National Research Institute of Astronomy and Geophysics, Helwan Cairo, Egypt

    Farouk M. Mahmoud

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  1. Farouk M. Mahmoud
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Mahmoud, F.M. Temperature variations of one well-known UV ceti type flare star. Astrophys Space Sci 234, 107–123 (1995). https://doi.org/10.1007/BF00627286

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  • DOI: https://doi.org/10.1007/BF00627286

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