Colliding stellar winds in the eclipsing Wolf-Rayet binary V444 Cygni

Shore, Steven N.; Brown, Douglas

doi:10.1086/166894

Cited by 62 publications

(42 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The presence of intra-binary structures causes variations in the emission line profiles with orbital phase (e.g. Shore & Brown 1988;Wiggs & Gies 1993). The high densities reached in the colliding wind region are thought to enable the formation of dust, explaining the large infrared emission from binary systems with WR stars (Williams et al 1987;Usov 1991), and the formation of spiral structures extending to distances of up to 300 times the binary separation ("pinwheel nebulae", Tuthill et al 1999).…”

Section: Introductionmentioning

confidence: 99%

Impact of orbital motion on the structure and stability of adiabatic shocks in colliding wind binaries

Lamberts

Dubus

Lesur

et al. 2012

A&A

View full text Add to dashboard Cite

Context. The collision of winds from massive stars in binaries results in the formation of a double-shock structure with observed signatures from radio to X-rays. Aims. We study the structure and stability of the colliding wind region as it turns into a spiral owing to the orbital motion. We focus on adiabatic winds, where mixing between the two winds is expected to be restricted to the Kelvin-Helmholtz instability. Mixing of the Wolf-Rayet wind with hydrogen-rich material is important for dust formation in pinwheel nebulae such as WR 104, where the spiral structure has been resolved in infrared. Methods. We use the hydrodynamical code RAMSES to solve the equations of hydrodynamics on an adaptive grid. A wide range of binary systems with different wind velocities and mass-loss rates are studied with two-dimensional simulations. A specific threedimensional simulation is performed to model WR 104. Results. Orbital motion leads to the formation of two distinct spiral arms where the Kelvin-Helmholtz instability develops differently. We find that the spiral structure is destroyed when there is a large velocity gradient between the winds, unless the collimated wind is much faster. We argue that the Kelvin-Helmholtz instability plays a major role in determining whether the structure is maintained. We discuss the consequences for various colliding-wind binaries. When their spiral structure is stable, there is no straightforward relationship between the spatial step of the spiral, the wind velocities, and the orbital period. Our 3D simulation of WR 104 indicates that the colder, well-mixed trailing arm has more favourable conditions for dust formation than the leading arm. The single-arm infrared spiral follows more closely the mixing map than the density map, suggesting that the dust-to-gas ratio may vary between the leading and trailing density spirals. However, the density is much lower than what dust formation models require. Including radiative cooling would lead to higher densities, and also to thin shell instabilities whose impact on the large-scale structure remains unknown.

show abstract

Section: Introductionmentioning

confidence: 99%

Impact of orbital motion on the structure and stability of adiabatic shocks in colliding wind binaries

Lamberts

Dubus

Lesur

et al. 2012

A&A

View full text Add to dashboard Cite

show abstract

“…V444Cygni (WR139, WN5+06III-V, P=4.21 d, e=O.04) Colliding wind effects in V444 Cygni have been well documented in the UV and optical (Shore & Brown 1988;Marchenko et al 1997;Flores et al 2001). It was expected that V444 Cyg would exhibit colliding wind X-ray emission at a level Lx~10 34 -35 erg s"!…”

Section: Colliding Wind X-ray Emissionmentioning

confidence: 98%

X-ray observations of massive colliding wind binaries

Corcoran

2003

Symp. - Int. Astron. Union

View full text Add to dashboard Cite

Abstract. Masslve stars in binary systems can generate X-ray emission in the region between the two stars where stellar winds collide. Colliding wind X-ray emission acts as an in-situ probe of important wind parameters like massloss rates, chemical abundances, wind velocities, and possibly magnetic field strengths. Variations in observed colliding-wind X-ray emission can be produced by the changing line-of-sight to the colliding wind region as the stars move in orbit and/or the changing emission measure of the shocked gas in the wind collision zone produced if the separations between the two stars change. X-ray variability depends on the wind and orbital parameters and so can in principal allow the direct measurement of mass functions even for low inclination systems and provide a connection between the stellar and wind parameters. X-rayemission from colliding wind systems can thus be used to refine our understanding of the evolutionary state of massive stars and to help test evolutionary models. We discuss recent advances in defining the X-ray spectral and temporal signatures of colliding wind X-ray emission using ROSAT~ASCA, RXTE~Chandra and XMM-Newton data.

show abstract

“…Early physical models for the WWC region were developed by Huang & Weigert (1982), Girard & Willson (1987), and Shore & Brown (1988). Using simple ram pressure balance arguments, they were able to predict, for isotropic and steady winds, the approximate locations and shapes of the WWC regions by assuming that they are infinitely thin and by neglecting Coriolis forces from the orbital motions of the two stars.…”

Section: Colliding Wind Binaries: Observations and Theorymentioning

confidence: 99%

Colliding winds in low-mass binary star systems: wind interactions and implications for habitable planets

Johnstone

Жилкин

Pilat-Lohinger

et al. 2015

A&A

View full text Add to dashboard Cite

Context. In binary star systems, the winds from the two components impact each other, leading to strong shocks and regions of enhanced density and temperature. Potentially habitable circumbinary planets must continually be exposed to these interaction regions. Aims. We study, for the first time, the interactions between winds from low-mass stars in a binary system to show the wind conditions seen by potentially habitable circumbinary planets. Methods. We use the advanced 3D numerical hydrodynamic code Nurgush to model the wind interactions of two identical winds from two solar mass stars with circular orbits and a binary separation of 0.5 AU. As input into this model, we use a 1D hydrodynamic simulation of the solar wind, run using the Versatile Advection Code. We derive the locations of stable and habitable orbits in this system to explore what wind conditions potentially habitable planets will be exposed to during their orbits. Results. Our wind interaction simulations result in the formation of two strong shock waves separated by a region of enhanced density and temperature. The wind-wind interaction region has a spiral shape due to Coriolis forces generated by the orbital motions of the two stars. The stable and habitable zone in this system extends from ∼1.4 AU to ∼2.4 AU. Habitable planets have to pass through strong shock waves several times per orbit and spend a significant amount of time embedded in the higher density matter between the shocks. The enhanced density in the wind-wind interaction region is likely to lead to a 20% decrease in the size of a planet's magnetosphere. Conclusions. Our results indicate that wind-wind interactions are likely to influence the magnetospheres and upper atmospheres of circumbinary planets and could have moderate implications for the development of habitable planetary environments.

show abstract

Colliding stellar winds in the eclipsing Wolf-Rayet binary V444 Cygni

Cited by 62 publications

References 12 publications

Impact of orbital motion on the structure and stability of adiabatic shocks in colliding wind binaries

Impact of orbital motion on the structure and stability of adiabatic shocks in colliding wind binaries

X-ray observations of massive colliding wind binaries

Colliding winds in low-mass binary star systems: wind interactions and implications for habitable planets

Contact Info

Product

Resources

About