Related papers: Eta Carinae and the Luminous Blue Variables
We predict quantitative mass-loss rates and terminal wind velocities for early-type supergiants and luminous blue variables (LBVs) using a dynamical version of the Monte Carlo radiative transfer method. First, the observed drop in terminal…
Spectra (1951-78) of the central object in eta Car, taken by A.D. Thackeray, reveal three previously unrecorded epochs of low excitation. Since 1948, at least, these states have occurred regularly in the 2020 day cycle proposed by Damineli…
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…
We perform a study on the optical and infrared photometric properties of known luminous blue variables (LBVs) in M31 using the sample of LBV candidates from the Local Group Galaxy Survey (Massey et al. 2007). We find that M31 LBV candidates…
Massive evolved stars in transition phases, such as Luminous Blue Variables (LBVs), B[e] Supergiants (B[e]SGs), and Yellow Hypergiants (YHGs), are not well understood, and yet crucial steps in determining accurate stellar and galactic…
We analyze interferometric measurements of the Luminous Blue Variable Eta Carinae with the goal of constraining the rotational velocity of the primary star and probing the influence of the companion. Using 2-D radiative transfer models of…
Major stellar-wind emission features in the spectrum of Eta Car have recently decreased by factors of order 2 relative to the continuum. This is unprecedented in the modern observational record. The simplest, but unproven, explanation is a…
Far-infrared Herschel PACS imaging and spectroscopic observations of the nebula around the luminous blue variable (LBV) star AG Car have been obtained along with optical imaging in the Halpha+[NII] filter. In the infrared light, the nebula…
The Luminous Blue Variable (LBV) R71 is currently undergoing an eruption, which differs photometrically and spectroscopically from its last outburst in the 1970s. Valuable information on the physics of LBV eruptions can be gained by…
The nature of SN 1961V has been uncertain. Its peculiar optical light curve and slow expansion velocity are similar to those of super-outbursts of luminous blue variables (LBVs), but its nonthermal radio spectral index and declining radio…
The periodicity of 5.5 years for some observational events occurring in Eta Carinae manifests itself across a large wavelength range and has been associated with its binary nature. These events are supposed to occur when the binary…
In this series of papers we have presented the results of a spectroscopic survey of luminous and variable stars in the nearby spirals M31 and M33. In this paper, we present spectroscopy of 132 additional luminous stars, variables, and…
We discuss moderate resolution spectra, multicolor photometry, and light curves of thirty-one of the most luminous stars and variables in the giant spiral M101. The majority are intermediate A to F-type supergiants. We present new…
CONTEXT: The RAVE spectroscopic survey for galactic structure and evolution obtains 8400-8800 Ang spectra at 7500 resolving power at the UK Schmidt Telescope using the 6dF multi-fiber positioner. More than 300,000 9<I<12 and |b|>25 deg…
We describe a search for H-alpha emission-lined stars in M31, M33, and seven dwarfs in or near the Local Group (IC 10, NGC 6822, WLM, Sextans B, Sextans A, Pegasus and the Phoenix dwarf) using interference filter imaging with the KPNO and…
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…
We present XMM-Newton observations of the luminous star Eta Carinae, including a high resolution soft X-ray spectrum of the surrounding nebula obtained with the Reflection Grating Spectrometer. The EPIC image of the field around Eta Car…
Understanding the late-stage evolution of the most massive stars such as $\eta$ Carinae is challenging because no true analogs of $\eta$ Car have been clearly identified in the Milky Way or other galaxies. In Khan et. al. (2013), we…
Blue supergiants (BSGs) mediate between the main sequence and the late stages of massive stars, which makes them valuable for assessing the physics that drives the stars across the diverse evolutionary channels. By exploring correlations…
Eta Carinae is considered to be a massive colliding wind binary system with a highly eccentric (e \sim 0.9), 5.54-yr orbit. However, the companion star continues to evade direct detection as the primary dwarfs its emission at most…