Related papers: Luminous Blue Variable candidates in M31
We have found three new LBV candidates in the star-forming galaxy NGC 4736. They show typical well-known LBV spectra, broad and strong hydrogen lines, He I lines, many Fe II lines, and forbidden [Fe II] and [Fe III]. Using archival Hubble…
We study the luminous blue variable candidate J004229.87+410551.8 in the Andromeda Galaxy. Earlier, the star displayed a spectral anomaly: although a hot emission spectrum had been detected, it had strong CaII H and K absorption lines.…
We present two new luminous blue variable (LBV) candidate stars discovered in the M33 galaxy. We identified these stars (Valeev et al. 2010) as massive star candidates at the final stages of evolution, presumably with a notable interstellar…
We present a new luminous star in M33 located in the nuclear region. The star shows strong FeII and [FeII] forest, hydrogen emissions in the spectrum, as well as nebular lines. TiII and SiII lines were detected in absorption, their radial…
The luminous blue variable (LBV) stars are peculiar very massive stars. The study of these stellar objects and their surroundings is important for understanding the evolution of massive stars and its effects on the interstellar medium. We…
In the current paper, we present a study of the spatial distribution of luminous blue variables (LBVs) and various LBV candidates (cLBVs) with respect to OB associations in the M33 galaxy. The identification of blue star groups was based on…
The evolutionary relationships and mechanisms governing the behavior of the wide variety of luminous stars populating the upper H-R diagram are not well established. Luminous blue variables (LBVs) are particularly rare, with only a few…
Massive stars typically undergo short-lived post-main sequence evolutionary phases with strong mass loss and occasional mass eruptions. Many of such massive stars in transition phases have been identified based on their dusty envelopes. The…
We report the results of optical spectroscopy of the candidate evolved massive star MN44 revealed via detection of a circular shell with the Spitzer Space Telescope. First spectra taken in 2009 May--June showed the Balmer lines in emission…
We continue to search for LBV stars in galaxies outside the Local Group. In this work, we have investigated four luminous stars in NGC 4449. Multiple spectral observations carried out for J122810.94+440540.6, J122811.70+440550.9, and…
We present the first four years of BVRI photometry from an on-going survey to annually monitor the photometric behavior of evolved luminous stars in M31 and M33. Photometry was measured for 199 stars at multiple epochs, including 9 classic…
In a recent paper, Smith and Tombleson (2015) state that the Luminous Blue Variables (LBVs) in the Milky Way and the Magellanic Clouds are isolated; that they are not spatially associated with young O-type stars. They propose a novel…
We continue the search for luminous blue variables (LBVs) in Local Volume galaxies in order to study their fundamental parameters. In this paper, we report the discovery of two new LBVs in the dwarf irregular galaxy NGC 1156. Both stars…
The upper region of the Hertzsprung-Russell diagram is populated by massive stars in a diversity of evolutionary stages, and the classification of these stars is often based on observed characteristics exclusively in the optical spectral…
The luminous blue variable (LBV) phase is a poorly understood stage in the evolution of high mass stars, characterized for its brevity and instability. The surroundings of LBV stars are excellent test beds to study their dense stellar winds…
Only about 19 Galactic and 25 extra-galactic bona-fide Luminous Blue Variables (LBVs) are known to date. This incomplete census prevents our understanding of this crucial phase of massive star evolution which leads to the formation of heavy…
Context. Luminous blue variables (LBVs) are rare massive stars with very high luminosity. They are characterized by strong photo-metric and spectroscopic variability related to transient eruptions. The mechanisms at the origin of these…
Luminous Blue Variables (LBVs) are enigmatic, evolved, massive stars. Their variability has been observed to be episodic with large eruptions, along with variations on time-scales of days to decades. We have extracted light curves of 37…
Recent IR surveys of the Galactic plane have revealed a large number of candidate Luminous Blue Variables. In order to verify these classifications we have been undertaking a long term spectroscopic and photometric monitoring campaign…
Luminous Blue Variables (LBVs) are a class of massive blue supergiants exhibiting irregular and eruptive instability, sometimes accompanied by extreme mass loss. While they have often been considered to be a brief but very important…