The system consists of a hydrogen deficient Wolf-Rayet (W-R) star
(center) and an O-type star, and their masses are about 10 and 25
solar mass respectively. A Wolf-Rayet star has very strong
stellar wind with its speed in order of 10^3 km/s, and a
O-star's wind speed is order of 10^2 km/s.
The two winds are colliding with each other and forming a
bow-shock which is compressed toward the O star. Because of the
fast
orbital motion (orbital period is about 4 days) and the turbulence,
the shape of the shock front will not be cylindrically symmetric.
This is one of the reason we have used a 3D instead of 2D simulation.
The polarization variation computed as a function of the orbital phase
will give us an estimated of mass-loss late of the W-R star.
The more
accurate estimate of mass-loss rate at W-R star stage is very
important 1. to predict the massive star's evolutionary track,
and
2. to model the "metalicity" of a galaxy, that is, to model
the chemical evolution a galaxy in cosmological time scale.
Ryuichi Kurosawa
(Please send me an e-mail for a comment, a question or a suggestion
to
kurosawa@phyast.pitt.edu)