Related papers: The prototype colliding-wind pinwheel WR 104
Studying the appearance and properties of bipolar winds is critical to understand the stellar evolution from the AGB to the planetary nebula (PN) phase. Many uncertainties exist regarding the presence and role of binary stellar systems,…
WR140 (WC7pd + O5) is often considered to be the archetype of hot, luminous colliding-wind binaries, with strong cyclic high-energy and dust-formation events. The challenge is that this system is quite extreme, with a long period (nearly an…
We present the results of an optical spectroscopic study of the massive Wolf-Rayet binary WR137. These data cover the dust-formation maximum in 1997. Combining all available measurements of radial velocities, we derive, for the first time,…
This paper discusses our ongoing efforts to characterize dust-enshrouded Wolf-Rayet (WR) stars in the radio and infrared. We have used the Very Large Array to measure the broadband radio spectrum of WR stars in suspected binary systems and…
High-resolution radio observations have revealed that non-thermal radio emission in WR stars arises where the stellar wind of the WR star collides with that of a binary companion. These colliding-wind binary (CWB) systems offer an important…
$\eta$ 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…
We present a time-lapse sequence of 20 near-infrared (J- and K'-band) snapshots of the central 20x20 arcsec of the Crab pulsar wind nebula, taken at subarcsecond resolution with the Hokupa'a/QUIRC adaptive optics camera on the Gemini North…
This work presents three dimensional, magneto-hydrodynamical simulations of the formation and early evolution of a subgroup of planetary nebulae that exhibit a variety of point-symmetric structures. For bipolar nebulae, the formation of…
Some carbon-rich Wolf-Rayet stars (WC stars) show an infrared excess from dust emission. Dust forms in the collision of the WC wind with a companion star's wind. As this dust is carried towards the ISM at close to the WCd wind speed and the…
We summarize the results of a multiwavelength observing campaign on the massive eclipsing binary CPD-41deg7742, another remarkable object in the young open cluster NGC 6231. Our campaign relies on high resolution echelle spectroscopy,…
The velocity and density distribution of $e^\pm$ in the pulsar wind are crucial distinction among magnetosphere models, and contains key parameters determining the high energy emission of pulsar binaries. In this work, a direct method is…
PSR B0656+14 is a middle-aged pulsar with a characteristic age $\tau_c=110$ kyr and spin-down power $\dot{E}= 3.8\times 10^{34}$ erg s$^{-1}$. Using Chandra data, we searched for a pulsar wind nebula (PWN) and found evidence of extended…
Eta Carinae, the closest, active, massive binary containing a highly unstable LBV, exhibits expanding, compressed wind shells, seen in emission, that are spatially and spectrally resolved by \hst/\stis. Starting in June 2009, these…
Binary systems with an accreting compact object are a unique chance to investigate the strong, clumpy, line-driven winds of early type supergiants by using the compact object's X-rays to probe the wind structure. We analyze the…
Our understanding of Pulsar Wind Nebulae (PWNe), has greatly improved in the last years thanks to unprecedented high resolution images taken from the HUBBLE, CHANDRA and XMM satellites. The discovery of complex but similar inner features,…
WR+O star binary systems exhibit synchrotron emission arising from relativistic electrons accelerated where the wind of the WR star and that of its massive binary companion collide - the wind-collision region (WCR). These ``colliding-wind''…
For pulsars similar to the one in the Crab Nebula, most of the energy input to the surrounding wind nebula occurs on a timescale of less than 1000 years; during this time, the nebula expands into freely expanding supernova ejecta. On a…
We use new and archival Chandra and ROSAT data to study the time variability of the X-ray emission from the pulsar wind nebula (PWN) powered by PSR B1509-58 on timescales of one week to twelve years. There is variability in the size,…
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,…
In this contribution we review the recent progress in the modeling of Pulsar Wind Nebulae (PWN). We start with a brief overview of the relevant physical processes in the magnetosphere, the wind-zone and the inflated nebula bubble. Radiative…