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WR146 - observing the OB-type companion

Sean M. Dougherty·P. M. Williams·D. L. Pollacco
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Abstract

We present new radio and optical observations of the colliding-wind system WR146 aimed at understanding the nature of the companion to the Wolf-Rayet star and the collision of their winds. The radio observations reveal emission from three components: the WR stellar wind, the non-thermal wind-wind interaction region and, for the first time, the stellar wind of the OB companion. This provides the unique possibility of determining the mass-loss rate and terminal wind velocity ratios of the two winds, independent of distance. Respectively, these ratios are determined to be 0.20+/-0.06 and 0.56+/-0.17 for the OB-companion star relative to the WR star. A new optical spectrum indicates that the system is more luminous than had been believed previously. We deduce that the ``companion'' cannot be a single, low luminosity O8 star as previously suggested, but is either a high luminosity O8 star, or possibly an O8+WC binary system.

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Sean M. Dougherty, P. M. Williams, D. L. Pollacco. 2000-03-03. WR146 - observing the OB-type companion. https://doi.org/10.1046/j.1365-8711.2000.03504.x

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