Related papers: Multi-Wavelength Observations of Colliding Stellar…
We have analysed the X-ray emission from a sample of close WR+O binaries using data from the public Chandra and XMM-Newton archives. Global spectral fits show that two-temperature plasma is needed to match the X-ray emission from these…
We present two-dimensional, cylindrically symmetric simulations of hydrodynamic and magnetohydrodynamic (MHD) wide-angle winds interacting with a collapsing environment. These simulations have direct relevance to young stellar objects…
In the present paper we discuss a selection of facts and questions related to observations and evolutionary calculations of massive single stars and massive stars in interacting binaries. We focus on the surface chemical abundances, the…
Photospheric radiation momentum is efficiently transferred by absorption through metal lines to the gaseous matter in the atmospheres of massive stars, sustaining strong winds and mass loss rates. Not only is this critical for the evolution…
Understanding the complex behavior of High Mass X-ray binaries (HMXBs) is not possible without detailed information about their donor stars. While crucial, this turns out to be a challenge on multiple fronts. First, multi-wavelength…
Massive stars in binary systems (as WR140, WR147 or $\eta$ Carinae) have long been regarded as potential sources of high-energy $\gamma$-rays. The emission is thought to arise in the region where the stellar winds collide and produce…
Binary systems containing a massive star and a non-accreting pulsar present strong interaction between the stellar and the pulsar winds. The properties of this interaction, which largely determine the non-thermal radiation in these systems,…
Clumping in hot star winds can significantly affect estimates of mass-loss rates, the inferred evolution of the star and the environmental impact of the wind. A hydrodynamical simulation of a colliding winds binary (CWB) with clumpy winds…
Wolf-Rayet stars embody the final stable phase of the most massive stars immediately before their evolution is terminated in a supernova explosion. They are responsible for some of the most extreme and energetic phenomena in stellar…
Gamma-ray binaries are colliding wind binaries (CWB) composed of a massive star a non-accreting pulsar with a highly relativistic wind. Particle acceleration at the shocks results in emission going from extended radio emission to the…
High-mass binaries hosting young pulsars can be powerful gamma-ray emitters. The stellar wind of the massive star in the system is expected to be clumpy. Since the high-energy emission comes from the pulsar-star wind interaction, the…
We present theoretical X-ray line profiles from a range of model colliding wind systems. In particular, we investigate the effects of varying the stellar mass-loss rates, the wind speeds, and the viewing orientation. We find that a wide…
Using XMM-Newton, we undertook a dedicated project to search for X-ray bright wind-wind collisions in 18 WR+OB systems. We complemented these observations with Swift and Chandra datasets, allowing for the study of two additional systems. We…
We investigate the hydrodynamics of two identical hypersonic stellar winds in a binary system. The interaction of these winds manifests itself in the form of two shocks and a contact surface between them. We neglect the binary rotation and…
Aspects of the wind-dynamics in symbiotic binaries, colliding winds and accretion, are reviewed. Inconsistencies between theory and observations of the hot star wind are discussed. If the hot star wind were governed by CAK theory, nearly…
The consequences of structured flows continue to be a pressing topic in relating spectral data to physical processes occurring in massive star winds. In a preceding paper, our group reported on hydrodynamic simulations of hypersonic flow…
Binaries with hot massive components are strong X-ray sources. Besides the intrinsic X-ray emission of individual binary members originating in their winds, X-ray emission stems from the accretion on the compact companion or from wind…
The clumping of massive star winds is an established paradigm confirmed by multiple lines of evidence and supported by stellar wind theory. The purpose of this paper is to bridge the gap between detailed models of inhomogeneous stellar…
Previous generations of X-ray observatories revealed a group of massive binaries that were relatively bright X-ray emitters. This was attributed to emission of shock-heated plasma in the wind-wind interaction zone located between the stars.…
The effects of nonequilibrium ionization are explicitly taken into account in a numerical model which describes colliding stellar winds (CSW) in massive binary sytems. This new model is used to analyze the most recent X-ray spectra of the…