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arXiv · 0902.4105

Dust formation by the colliding-wind WC5+O9 binary WR19 at periastron passage

P. M. Williams·G. Rauw·K. A. van der Hucht
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Abstract

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.

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P. M. Williams, G. Rauw, K. A. van der Hucht. 2009-02-24. Dust formation by the colliding-wind WC5+O9 binary WR19 at periastron passage. https://doi.org/10.1111/j.1365-2966.2009.14681.x

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