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The Wolf-Rayet (WR) bubble S 308 around the WR star HD 50896 is one of the only two WR bubbles known to possess X-ray emission. We present XMM-Newton observations of three fields of this WR bubble that, in conjunction with an existing observation of its Northwest quadrant, map most of the nebula. The X-ray emission from S 308 displays a limb-brightened morphology, with a central cavity ~22 arcmin in size and a shell thickness of ~8 arcmin. This X-ray shell is confined by the optical shell of ionized material. The spectrum is dominated by the He-like triplets of NIV at 0.43 keV and OVII at 0.57 keV, and declines towards high energies, with a faint tail up to 1 keV. This spectrum can be described by a two-temperature optically thin plasma emission model (T1 ~ 1.1x10^6 K, T2 ~ 13x10^6 K), with a total X-ray luminosity ~2x10^33 erg/s at the assumed distance of 1.5 kpc.
Using a code that employs a self-consistent method for computing the effects of photoionization on circumstellar gas dynamics, we model the formation of wind-driven nebulae around massive Wolf-Rayet (W-R) stars. Our algorithm incorporates a simplifie
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 also impr
Dense populations of stars surround the nuclear regions of galaxies. In this work, we study the interaction of a WR star with relativistic jets in active galactic nuclei. A bow-shaped double-shock structure will form as a consequence of the interacti
We present mid-infrared spectrophotometric observations of SS433 with ISOPHOT. The HeI+HeII lines in both spectra of SS433 and of the Wolf-Rayet star WR147, a wind-colliding WN8+BO5 binary system, closely match. The 2.5-12 micron continuum radiation
With a deep Chandra/HETGS exposure of WR 6, we have resolved emission lines whose profiles show that the X-rays originate from a uniformly expanding spherical wind of high X-ray-continuum optical depth. The presence of strong helium-like forbidden li