Abstract

2009: a Colliding-wind Odyssey

Rémi Fahed (Université de Montréal)

A. F. J. Moffat (Université de Montréal) J. Zorec (IAP) T. Eversberg (Schnorringen Telescope Science Institute) A. N. Chené (Universidad de Concepcion) M. F. Corcoran (NASA/GSFC) S. M. Dougherty (HIA) J. M. Pittard (University of Leeds) A. M. T. Pollock (ESA) P. M. Williams (Royal Observatory of Edinburgh) the MONS team

We present the results from two optical spectroscopic campaigns on colliding-wind binaries which both happened in 2009. The first one was on WR 140 (WC7pd + O5.5fc), a.k.a. "the CWB archetype", which experienced periastron passage of its highly elliptical 8-year orbit in January (along with eta Car, as it turned out). The WR140 campaign consisted of a unique and constructive collaboration between amateur and professional astronomers and took place at half a dozen locations, including Teide Observatory, Observatoire de Haute Provence, Dominion Astrophysical Observatory, Observatoire du Mont Megantic and at several small private observatories. The second campaign on a selection of 6 short-period WR+O binaries (or suspected binaries) not yet studied for colliding-wind effects (as well as periastron passage of 2 medium period systems) took place at Leoncito Observatory, Argentina, during 1 month. We provide updated values of most of these systems for the orbital parameters, new estimates for the WR and O star masses and new constraints on the mass-loss rates and colliding wind geometry.

Mode of presentation: poster