Miras or SRA'S - the Transient Type Variables

Abstract

The group of Mira-type and semi-regular variables with similar periodicity (multiperiodicty) is analyzed. They have periods of 230-260 days and 140-150 days and show intervals of periodical (Mira-type) variability with relatively high amplitude and "semi-regular" (SR-type) small-amplitude oscillations. Results of periodogram analysis are represented.Comment: 5 pages, 3 figures, 1 table, to appear in Cz{\ke}stochowski Kalendarz Astronomiczny 2014, ed. Bogdan Wszo{\l}ek et a