The Double-lined Spectrum of LBV 1806–20

  title={The Double-lined Spectrum of LBV 1806–20},
  author={Donald F. Figer and Francisco Najarro and Rolf Peter Kudritzki},
  journal={The Astrophysical Journal Letters},
  pages={L109 - L112}
Despite much theoretical and observational progress, there is no known firm upper limit to the masses of stars. Our understanding of the interplay between the immense radiation pressure produced by massive stars in formation and the opacity of infalling material is subject to theoretical uncertainties, and many observational claims of "the most massive star" have failed the singularity test. LBV 1806-20 is a particularly luminous object, L ∼ 106 L⊙, for which some have claimed very high mass… 

Massive Stars in the SGR 1806-20 Cluster

We report the discovery of additional hot and massive stars in the cluster surrounding the soft gamma repeater SGR 1806-20, based on United Kingdom Infrared Telescope and Keck near-infrared

Constraints on the Distance to SGR 1806–20 from H I Absorption

The giant flare detected from the magnetar SGR 1806-20 on 2004 December 27 had a fluence more than 100 times higher than the only two other soft gamma repeater (SGR) flares ever recorded. Whereas the

The Outcome of the Protoplanetary Disk of Very Massive Stars

An exceptionally bright flare from SGR 1806–20 and the origins of short-duration γ-ray bursts

Soft-γ-ray repeaters (SGRs) are galactic X-ray stars that emit numerous short-duration (about 0.1 s) bursts of hard X-rays during sporadic active periods. They are thought to be magnetars: strongly

Detection of a radio counterpart to the 27 December 2004 giant flare from SGR 1806–20

The energetics and the rapid decay of the radio source are not compatible with the afterglow model that is usually invoked for γ-ray bursts, and it is suggested that the rapidly decaying radio emission arises from the debris ejected during the explosion.

Luminous Blue Variables

Luminous Blue Variables are massive evolved stars, here we introduce this outstanding class of objects. Described are the specific characteristics, the evolutionary state and what they are connected

The Massive Star Population at the Center of the Milky Way

Abstract Recent detection of a large number of apparently isolated massive stars within the inner 80 pc of the Galactic Center has raised fundamental questions regarding massive star formation in a

Luminous blue variables: An imaging perspective on their binarity and near environment

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

A downward revision to the distance of the 1806-20 cluster and associated magnetar from Gemini Near-Infrared Spectroscopy

We present H- and K-band spectroscopy of OB and Wolf–Rayet (WR) members of the Milky Way cluster 1806−20 (G10.0–0.3) to obtain a revised cluster distance, of relevance to the 2004 giant flare from

On the population of galactic Luminous Blue Variables

We report the first results of a long term infrared monitoring campaign of known and candidate galactic Luminous Blue Variables (LBVs). In particular, we are able to confirm the LBV nature of



Optical and Infrared Observations of SGR 1806-20

The soft gamma-ray repeater (SGR) 1806-20 is associated with the center-brightened nonthermal nebula Gl0.0-0.3, thought to be a plerion. As in other plerions, a steady X-ray source, AX 1805.7-2025,

The Pistol Star

We present new near-infrared data and analysis, which indicate that the Pistol Star is one of the most luminous stars known, adding another test point for massive star formation and stellar evolution

A Luminous Companion to SGR 1806-20

We have obtained infrared spectra of the star suggested to be the counterpart of the soft gamma-ray repeater (SGR) 1806-20. We found strong emission lines similar to those seen in the spectra of the

In hot pursuit of the hidden companion of η Carinae: an X-ray determination of the wind parameters

We present X-ray spectral ts to a recently obtained Chandra grating spectrum of Carinae, one of the most massive and powerful stars in the Galaxy and which is strongly suspected to be a colliding

Massive Stars in the Quintuplet Cluster

We present near-infrared photometry and K-band spectra of newly identified massive stars in the Quintuplet cluster, one of the three massive clusters projected within 50 pc of the Galactic center. We

Eta Carinae: a long period binary?

Evidence for a fundamental stellar upper mass limit from clustered star formation, and some implications therof

Theoretical considerations lead to the expectation that stars should not have masses larger than about $m_{\rm max*}=60$–$120M_\odot$, while the observational evidence has been ambiguous. Only very

Hubble Space Telescope/NICMOS Observations of Massive Stellar Clusters near the Galactic Center

We report Hubble Space Telescope (HST) Near-Infrared Camera and Multiobject Spectrometer (NICMOS) observations of the Arches and Quintuplet clusters, two extraordinary young clusters near the

WR 20a: a massive cornerstone binary system comprising two extreme early-type stars ⋆

We analyse spectroscopic observations of WR 20a revealing that this star is a massive early-type binary system with a most probable orbital period of ∼3.675 days. Our spectra indicate that both

η Carinae: Binarity Confirmed

Although deviations from a simple case exist around periastron, intensive monitoring during the next event (mid-2003) will be crucial to the understanding of the system, implying that the energy and dynamics of the event repeat from cycle to cycle.