Secular Variations of the Photometric Parameters of Mira Ceti Variables and Semiregular Variables

摘要

The photometric properties of long-period variable stars and problems related to their traditional classification are analyzed. A general review of secular variations of such light-curve parameters studied in our previous papers as the period, amplitude, and mean brightness is given. Several types of Mira Ceti stars that differ in the secular period variation pattern are identified. A connection between the secular amplitude variations of certain variables with the effect of multiperiodicity is revealed. It is shown that the pattern of these variations and their numerical properties may be used to classify these variable stars.