Statistical Studies of Long - Period Variable Stars in Odessa

TL;DR

This paper presents a comprehensive statistical analysis of long-period variable stars, including classification, evolutionary status, and variability patterns, based on a century of observational data from multiple international sources.

Contribution

It offers a detailed classification of Mira-type, semi-regular, and symbiotic stars, and investigates their evolutionary links using extensive historical observational data.

Findings

Identification of correlations between photometric parameters

Detection of changes in light curve characteristics over time

Insights into the transitional variability between Mira-type and semi-regular stars

Abstract

The studies of pulsating variable stars are traditional subjects of astronomers in Odessa. In the last half of the 20th century, the studies of the physical variable stars were the topics of 15 PhD theses of the collaborators of the Odessa State (now National) University. Continuing the tradition of studies of long-period variable stars in the Astronomical Observatory of Odessa University, we try to conduct a detailed classification of the Mira-type stars, semi-regular variable stars and also find out the location of symbiotic stars among other long-period variables in their evolution to the planetary nebulae, using the compiled material from own observations and that of other authors. For the research, we have used observations from the databases of the French Association of Variable Stars Observers (AFOEV) and Variable Stars Observers League of Japan (VSOLJ), which allow study of the variability of these stars during the time interval of about 100 years. Some stars were studied using the observations of the American Association of Variable Star Observers (AAVSO). Modern research of long-period variable stars in Odessa is conducted in several directions: 1. The analysis of correlations between the photometric parameters. 2. The study of changes on time of individual characteristics of the light curves. 3. The study of variability of the objects which are transitional between the Mira-type and the semi-regular variables. The conclusions are discussed.