We present infrared photometry of the episodic dust-making Wolf-Rayet system WR19 (LS3), tracking its fading from a third observed dust-formation episode in 2007 and strengthening the view that these episodes are periodic (P = 10.1+/-0.1 y). Radial velocities of the O9 component observed between 2001 and 2008 show RV variations consistent with WC19 being a spectroscopic binary of high eccentricity (e=0.8), having periastron passage in 2007.14, shortly before the phase of dust formation. In this respect, WR19 resembles the archetypical episodic dust-making colliding-wind binary system WR140.
@article{arxiv.0902.4105,
title = {Dust formation by the colliding-wind WC5+O9 binary WR19 at periastron passage},
author = {P. M. Williams and G. Rauw and K. A. van der Hucht},
journal= {arXiv preprint arXiv:0902.4105},
year = {2014}
}
Comments
5 pages and 4 figures, accepted for publication in MNRAS