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Extraordinarily Hot X-ray Emission from the 09 Emission Line Star HD 119682

C. E. Rakowski·N. S. Schulz·S. J. Wolk·P. Testa
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Abstract

We present new optical and X-ray observations to show that the X-ray source 1 WGA J1346.5--6255 previously associated with the SNR G309.2--0.6 can be unequivocally identified with the emission line star HD 119682 located in the foreground open cluster NGC 5281. Images from Chandra in the X-ray band as well as from Magellan in the narrow optical H-alpha band show a coincidence of the source positions within 0.5". The X-ray source appears extremely hot for an OB-star identified as of O9.7e type. XMM-Newton spectra show plasma temperatures of 1 keV and >8 keV with an X-ray luminosity of 6.2E32 +/-0.1E32 erg/s. The optical and X-ray properties are very reminiscent of the prototype emission line star Gamma-Cas. We discuss the ramifications of this similarity with respect to very early type emission line stars as a new class of hard X-ray sources.

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C. E. Rakowski, N. S. Schulz, S. J. Wolk, P. Testa. 2006-08-15. Extraordinarily Hot X-ray Emission from the 09 Emission Line Star HD 119682. https://doi.org/10.1086/508350

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