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Related papers: A Lighthouse Effect in Eta Carinae

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We study colliding winds in the superluminous binary eta Carinae by performing three-dimensional, Smoothed Particle Hydrodynamics (SPH) simulations. For simplicity, we assume both winds to be isothermal. We also assume that wind particles…

$\eta$~Car is one of the most massive stars in the Galaxy. It underwent a massive eruption in the 19th century, which produced the impressive bipolar Homunculus nebula now surrounding it. The central star is an eccentric binary with a…

We study the usage of the X-ray light curve, column density toward the hard X-ray source, and emission measure (density square times volume), of the massive binary system Eta Carinae to determine the orientation of its semi-major axis. The…

Solar and Stellar Astrophysics · Physics 2015-05-13 Amit Kashi , Noam Soker

The stellar binary $\eta$ Carinae has been observed during its full orbital period in gamma rays by the Fermi-Large Area Telescope (LAT). The shock-accelerated electrons in the colliding winds of the two stars radiate synchrotron photons in…

High Energy Astrophysical Phenomena · Physics 2018-01-03 Nayantara Gupta , Soebur Razzaque

The X-ray emission of $\eta$ Carinae shows multiple features at various spatial and temporal scales. The central constant emission (CCE) component is centred on the binary and arises from spatial scales much smaller than the bipolar…

We report on high-resolution spectroscopy of the 2009.0 spectroscopic event of $\eta$ Carinae collected via SMARTS observations using the CTIO 1.5 m telescope and echelle spectrograph. Our observations were made almost every night over a…

Solar and Stellar Astrophysics · Physics 2015-09-23 Noel D. Richardson , Douglas R. Gies , Theodore R. Gull , Anthony F. J. Moffat , Lucas St-Jean

Recent work suggests that the mass-loss rate of the primary star (Eta A) in the massive colliding wind binary Eta Carinae dropped by a factor of 2-3 between 1999 and 2010. We present results from large- (r=1545au) and small- (r=155au)…

Spectral observations of the massive colliding wind binary Eta Carinae show phase-dependent variations, in intensity and velocity, of numerous helium emission and absorption lines throughout the entire 5.54-year orbit. Approaching…

Solar and Stellar Astrophysics · Physics 2015-06-24 Nicola Clementel , Thomas I. Madura , Chael J. H. Kruip , Jan-Pieter Paardekooper

We quantify the rapid variations in X-ray brightness ("flares") from the extremely massive colliding wind binary Eta Carinae seen during the past three orbital cycles by RXTE. The observed flares tend to be shorter in duration and more…

High Energy Astrophysical Phenomena · Physics 2014-11-20 A. F. J. Moffat , M. F. Corcoran

The interacting binary Eta Carinae remains one of the most enigmatic massive stars in our Galaxy despite over four centuries of observations. In this work, its light curve from the ultraviolet to the near-infrared is analysed using…

Eta Carinae shows broad peaks in near-infrared (IR) JHKL photometry, roughly correlated with times of periastron passage in the eccentric binary system. After correcting for secular changes attributed to reduced extinction from the thinning…

Solar and Stellar Astrophysics · Physics 2015-05-14 Nathan Smith

In gamma-ray binaries neutron star is orbiting a companion that produces a strong stellar wind. We demonstrate that observed properties of "stellar wind"-"pulsar wind" interaction depend both on the overall wind thrust ratio, as well as…

High Energy Astrophysical Phenomena · Physics 2024-06-26 Maxim V. Barkov , Evgeniy Kalinin , Maxim Lyutikov

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…

Solar and Stellar Astrophysics · Physics 2015-05-19 Jose H. Groh , Thomas I. Madura , Stanley P. Owocki , D. John Hillier , Gerd Weigelt

We argue that the asymmetric morphology of the blue and red shifted components of the outflow at hundreds of AU from the massive binary system Eta Carinae can be understood from the collision of the primary stellar wind with the slowly…

Solar and Stellar Astrophysics · Physics 2015-06-03 Noam Soker , Amit Kashi

The most massive binary system Eta Carinae has been recently established as a gamma-ray source by the AGILE and Fermi-LAT detectors. The high energy spectrum of this gamma-ray source is very intriguing. It shows two clear components and a…

High Energy Astrophysical Phenomena · Physics 2015-05-27 W. Bednarek , J. Pabich

Eta Carinae is the nearest example of a supermassive, superluminous, unstable star. Mass loss from the system is critical in shaping its circumstellar medium and in determining its ultimate fate. Eta Car currently loses mass via a dense,…

The asymmetric shape of the nebula around $\eta$-Carinae (Homunculus) can be explained by a spherical expansion in a non-homogeneous medium. Two models are analyzed: an exponential and an inverse power law dependence for the density as a…

Astrophysics of Galaxies · Physics 2011-09-20 Lorenzo Zaninetti

\eta\ Car is the only colliding-wind binary for which high-energy \gamma\ rays are detected. Although the physical conditions in the shock region change on timescales of hours to days, the variability seen at GeV energies is weak and on…

High Energy Astrophysical Phenomena · Physics 2015-06-23 S. Ohm , V. Zabalza , J. A. Hinton , E. R. Parkin

Context : If relativistic particle acceleration takes place in colliding-wind binaries, hard X-rays and gamma-rays are expected through inverse Compton emission, but to date these have never been unambiguously detected. Aims : To detect…

Astrophysics · Physics 2008-01-15 Jean-Christophe Leyder , Roland Walter , Gregor Rauw

We have made an extensive study of the UV spectrum of Eta Carinae, and find that we do not directly observe the star and its wind in the UV. Because of dust along our line of sight, the UV light that we observe arises from bound-bound…