Related papers: Modeling Forbidden Line Emission Profiles from Col…
Given their strong stellar winds, Wolf-Rayet (WR) stars exhibit emission line spectra that are predominantly formed in expanding atmospheric layers. The description of the wind velocity field $v(r)$ is therefore a crucial ingredient in the…
In the colliding wind region of early-type binaries, electrons can be accelerated up to relativistic energies displaying power-law spectra, as demonstrated by the detection of non-thermal radio emission from several WR+OB systems. The…
The migration of profile sub-peaks identified in time-monitored optical emission lines of Wolf-Rayet star spectra provides a direct diagnostic of the dynamics of their stellar winds via a measured line-of-sight velocity change per unit…
Our dedicated XMM-Newton monitoring, as well as archival Chandra and Swift datasets, were used to examine the behaviour of the WN5h+O3V binary WR21a at high energies. For most of the orbit, the X-ray emission exhibits few variations.…
Massive stars in binary systems have long been regarded as potential sources of high-energy gamma rays.The emission is principally thought to arise in the region where the stellar winds collide and accelerate relativistic particles which…
We present calculations of the spatial and spectral distribution of the radio emission from a wide WR+OB colliding-wind binary system based on high-resolution hydrodynamical simulations and solutions to the radiative transfer equation. We…
One of the main properties of Wolf-Rayet (WR) stars is a very intense outflow of gas. No less than 40\% \ of WR stars belong to binary systems. Young massive O and B stars are the secondary components of such systems. OB stars also have an…
Recent reports claiming tentative association of the massive star binary system gamma^2 Velorum (WR 11) with a high-energy gamma-ray source observed by Fermi-LAT contrast the so-far exclusive role of Eta Carinae as the hitherto only…
Colliding wind binaries (CWBs) are promising sources of high-energy gamma-ray emission driven by shock acceleration of particles at wind interaction zones. The nearby CWB system $\gamma^2$ Velorum (WR 11), composed of a Wolf-Rayet (WR) and…
We modelled the Chandra and RXTE X-ray spectra of the massive binary WR 140 in the framework of the standard colliding stellar wind (CSW) picture. Models with partial electron heating at the shock fronts are a better representation of the…
We analyze new high-resolution Chandra X-ray images of the Wolf-Rayet binary system WR147. This system contains a WN8 star with an early-type companion located 0.6'' to its north, and is the only known early-type binary with a separation on…
We examine the dependence of the wind-wind collision and subsequent X-ray emission from the massive WR+O star binary WR~22 on the acceleration of the stellar winds, radiative cooling, and orbital motion. Simulations were performed with…
Massive star winds are structured both stochastically ("clumps") and often coherently (Co-rotation Interaction Regions, or CIRs). Evidence for CIRs threading the winds of Wolf-Rayet (WR) stars arises from multiple diagnostics including…
The study of the X-ray line profiles produced by massive colliding wind binaries is a powerful tool for the characterisation of the stellar winds. We built a self-consistent program for the computation of line profiles named LIFELINE. The…
The X-ray emission from the super-massive star Eta Carinae is simulated using a three dimensional model of the wind-wind collision. In the model the intrinsic X-ray emission is spatially extended and energy dependent. Absorption due to the…
In this paper we derive stellar parameters for the Wolf-Rayet star in the gamma Velorum binary system (WR11), from a detailed non-LTE model of its optical and infrared spectra. Compared to the study of Schaerer et al., the parameters of the…
We have developed radiative transfer models of the radio emission from colliding-wind binaries (CWB) based on a hydrodynamical treatment of the wind-collision region (WCR). The archetype of CWB systems is the 7.9-yr period binary WR140,…
Because most massive stars have been or will be affected by a companion during the course of their evolution, we cannot afford to neglect binaries when discussing the progenitors of supernovae and GRBs. Analyzing linear polarization in the…
When two massive stars orbit each other, their winds create a shock cone. In some cases, an evolved, carbon-rich Wolf-Rayet (WR) star's wind collides with that of an orbiting OB star, condensing into dust downstream. This dust is then seen…
Colliding winds of massive star binary systems are considered as potential sites of non-thermal high-energy photon production. This is motivated merely by the detection of synchrotron radio emission from the expected colliding wind…