Abstract : | Luminous Blue Variables (LBVs) are unstable, evolved massive stars, and characterized by their frequent outburst activities. They show significant spectrophotometric variability over their outburst phase and exhibit a remarkable change in spectral type between the quiescent and outburst phases. These stars are generally hot supergiant which typically shows broad and strong hydrogen lines, He I, Fe II, and [Fe II] lines in their emission spectra along with P-Cygni profile as well as infra-red excess in their spectral energy distributions (SEDs). The driving mechanism of their outburst activities and the role of these activities in the evolution of massive stars are still not fully understood as there exists only a handful of LBVs in the Local Group. In this talk, I will discuss the photometric and spectroscopic evolution of these exotic stars in nearby galaxies and present the results of our monitoring of one such LBV, AF And, in the M31 galaxy.
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