Luminous blue variables (LBVs) are a class of highly unstable stars that have been proposed to play a critical role in massive stellar evolution as well as being the progenitors of some of the most luminous supernovae known. However the physical processes underlying their characteristic instabilities are currently unknown. In order to provide observational constraints on this behaviour we have ...

Abstract In this paper we analyze Sloan g, r, i archival imaging data of M33 taken by Hartman et al. using MegaCam at the Canada–France–Hawaii Telescope. To determine distance to galaxy, performed several analytical steps identify its Cepheid population. We used Lomb–Scargle algorithm find periodicity and visually identified 1989 periodic variable stars. Since Cepheids occupy a specific region ...

Key and still largely missing parameters for measuring the mass content and distribution of the Local Group are the proper motion vectors of its member galaxies. The problem when trying to derive the gravitational potential of the Local Group is that usually only radial velocities are known, and hence statistical approaches have to be used. The expected proper motions for galaxies within the Lo...

The number ratio of carbon-rich to oxygen-rich asymptotic giant branch (AGB) stars (the so-called C/M ratio) is closely related the evolution environment host galaxy. This work studies in 14 galaxies within Local Group with most complete and clean sample member identified our previous works. borderlines between AGB as well red supergiants are defined by Gaussian mixture model fitting density (J...