X-ray study on the nature of the colliding stellar winds in the massive star binary WR140

We analysed XMM-Newton RGS data of the colliding-wind massive star binary WR140 taken over 8 years. From the line-of-sight velosity of Ne Kα lines, we derived the distance of the Ne line-emission region from the stagnation point of the shock cone. We performed diagnostics of the electron number density with the He-like triplet of the Ne Kα line.