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An X-ray investigation of the NGC 346 field in the SMC (3): XMM-Newton data

Yaël Nazé·Jean Manfroid·Ian R. Stevens·Michael F. Corcoran·Aaron Flores
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Abstract

We present new XMM-Newton results on the field around the NGC346 star cluster in the SMC. This continues and extends previously published work on Chandra observations of the same field. The two XMM-Newton observations were obtained, respectively, six months before and six months after the previously published Chandra data. Of the 51 X-ray sources detected with XMM-Newton, 29 were already detected with Chandra. Comparing the properties of these X-ray sources in each of our three datasets has enabled us to investigate their variability on times scales of a year. Changes in the flux levels and/or spectral properties were observed for 21 of these sources. In addition, we discovered long-term variations in the X-ray properties of the peculiar system HD5980, a luminous blue variable star, that is likely to be a colliding wind binary system, which displayed the largest luminosity during the first XMM-Newton observation.

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Yaël Nazé, Jean Manfroid, Ian R. Stevens, Michael F. Corcoran, Aaron Flores. 2004-02-26. An X-ray investigation of the NGC 346 field in the SMC (3): XMM-Newton data. https://doi.org/10.1086/386323

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