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The Discovery of a Twelfth Wolf-Rayet Star in the Small Magellanic Cloud

Philip Massey·K. A. G. Olsen·J. Wm. Parker
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Abstract

We report the discovery of a relatively faint (V=15.5) early-type WN star in the SMC. The line strength and width of He II lambda 4686 emission is similar to that of the other SMC WNs, and the presense of N V lambda 4603,19 emission (coupled with the lack of N III) suggests this star is of spectral type WN3-4.5, and thus is similar in type to the other SMC WRs. Also like the other SMC WN stars, an early-type absorption spectrum is weakly present. The absolute magnitude is comparable to that of other (single) Galactic early-type WNs. The star is located in the Hodge 53 OB association, which is also the home of two other SMC WNs. This star, which we designate SMC-WR12, was actually detected at a high significance level in an earlier interference-filter survey, but the wrong star was observed as part of a spectroscopic followup, and this case of mistaken identity resulted in its Wolf-Rayet nature not being recognized until now.

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Philip Massey, K. A. G. Olsen, J. Wm. Parker. 2003-08-13. The Discovery of a Twelfth Wolf-Rayet Star in the Small Magellanic Cloud. https://doi.org/10.1086/379024

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