Astronomy and Astrophysics – Astrophysics
Scientific paper
2004-10-30
Mon.Not.Roy.Astron.Soc. 356 (2005) 1308-1326
Astronomy and Astrophysics
Astrophysics
22 pages, 14 figures. Accepted for publication in MNRAS
Scientific paper
10.1111/j.1365-2966.2004.08556.x
We present a new analysis of an archived Chandra HETGS X-ray spectrum of the WR+O colliding wind binary Gamma Velorum. The spectrum is dominated by emission lines from astrophysically abundant elements: Ne, Mg, Si, S and Fe. From a combination of broad-band spectral analysis and an analysis of line flux ratios we infer a wide range of temperatures in the X-ray emitting plasma (~4-40 MK). As in the previously published analysis, we find the X-ray emission lines are essentially unshifted, with a mean FWHM of 1240 +/- 30 km/s. Calculations of line profiles based on hydrodynamical simulations of the wind-wind collision predict lines that are blueshifted by a few hundred km/s. The lack of any observed shift in the lines may be evidence of a large shock-cone opening half-angle (> 85 degrees), and we suggest this may be evidence of sudden radiative braking. From the R and G ratios measured from He-like forbidden-intercombination-resonance triplets we find evidence that the Mg XI emission originates from hotter gas closer to the O star than the Si XIII emission, which suggests that non-equilibrium ionization may be present.
Henley David B.
Pittard Julian Mark
Stevens Ian R.
No associations
LandOfFree
Probing the wind-wind collision in Gamma Velorum with high-resolution Chandra X-ray spectroscopy: evidence for sudden radiative braking and non-equilibrium ionization does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Probing the wind-wind collision in Gamma Velorum with high-resolution Chandra X-ray spectroscopy: evidence for sudden radiative braking and non-equilibrium ionization, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Probing the wind-wind collision in Gamma Velorum with high-resolution Chandra X-ray spectroscopy: evidence for sudden radiative braking and non-equilibrium ionization will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-511111