Related papers: Explaining the transient fast blue absorption line…

We propose an explanation to the puzzling appearance of a wide blue absorption wing in the He I 10830A P-Cygni profile of the massive binary star Eta Carinae several months before periastron passage. Our basic assumption is that the…

We have monitored the massive binary star $\eta$ Carinae with the CTIO/SMARTS 1.5~m telescope and CHIRON spectrograph from the previous apastron passage of the system through the recent 2014.6 periastron passage. Our monitoring has resulted…

We examine a variety of observations that shed light on the orientation of the semi-major axis of the Eta Carinae massive binary system. Under several assumptions we study the following observations: The Doppler shifts of some He I P-Cygni…

We report near-IR spectroscopic observations of the Eta Carinae massive binary system during 2008-2009 using VLT/CRIRES. We detect a strong, broad absorption wing in He I 10833 extending up to -1900 km/s across the 2009.0 spectroscopic…

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…

$\eta$ Carinae is an extremely luminous and energetic colliding-wind binary. The combination of its orbit and orientation, with respect to our line of sight, enables direct investigation of the conditions and geometry of the colliding…

The highly eccentric binary system Eta Carinae shows numerous time-variable emission and absorption features. These observational signatures are the result of interactions between the complex three-dimensional (3D) wind-wind collision…

We argue that the emission and the absorption components of he N II lines recently observed in Eta Carinae can originate in the secondary's wind acceleration zone. We base this claim in part on the presence of these lines in hot nitrogen…

Contrary to recent claims, we argue that the orientation of the massive binary system Eta Carinae is such that the secondary star is closer to us at periastron passage, and it is on the far side during most of the time of the eccentric…

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…

Context. Colliding-wind binaries are massive stellar systems featuring strong, interacting winds. These binaries may be actual particle accelerators, making them variable gamma-ray sources due to changes in the wind collision region along…

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…

We present high resolution numerical simulations of the colliding wind system $\eta$ Carinae, showing accretion onto the secondary star close to periastron passage. Our hydrodynamical simulations include self gravity and radiative cooling.…

We study the propagation of the ionizing radiation emitted by the secondary star in Eta Carinae. We find that a large fraction of this radiation is absorbed by the primary stellar wind, mainly after it encounters the secondary wind and…

$\eta$ Carinae is a colliding wind binary hosting two of the most massive stars and featuring the strongest wind collision mechanical luminosity. The wind collision region of this system is detected in X-rays and $\gamma$-rays and offers a…

The exact nature of eta Carinae is still an open issue. In this paper we assume a binary system to explain the strong X-ray emission, but we also take into account that, near periastron and because of the highly eccentric orbit, the wind…

We show that recent observations of He I and N II lines of $\eta$ Carinae may provide support for an orbital orientation where the secondary star is closest to us at periastron passages. This conclusion is valid both for the commonly…

Eta Car, with its historical outbursts, visible ejecta and massive, variable winds, continues to challenge both observers and modelers. In just the past five years over 100 papers have been published on this fascinating object. We now know…

We continue to explore the accretion model of the massive binary system eta Carinae by studying the anomalously high He II 4686 line. The line appears just before periastron and disappears immediately thereafter. Based on the He II 4686…

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…