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arXiv · 1004.4101

Unveiling the nature of IGR J16493-4348 with IR spectroscopy

E. Nespoli·J. Fabregat·R. E. Mennickent
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Abstract

The International Gamma-Ray Astrophysics Laboratory (INTEGRAL) is discovering a large number of new hard X-ray sources, many of them being HMXBs. The identification and spectral characterization of their optical/infrared counterparts is a necessary step in undertaking a detailed study of these systems. In a previous paper, we presented spectral analyses and classifications of six newly discovered INTEGRAL sources. In this paper, we extend the analysis to IGR J16493-4348. We used the ESO/VLT ISAAC spectrograph to observe the proposed IR counterpart to the source, obtaining a Ks medium-resolution spectrum (R = 500) with a signal-to-noise ratio (S/N) >150. We classified the source by comparing with published atlases. We spectrally classified the source as a B0.5-1 supergiant and estimated its interstellar extinction. We compared the extinction derived from X-ray data with effective interstellar extinction obtained from our data, discussing the absorption component associated with the circumstellar environment.

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E. Nespoli, J. Fabregat, R. E. Mennickent. 2010-04-23. Unveiling the nature of IGR J16493-4348 with IR spectroscopy. https://doi.org/10.1051/0004-6361%2F201014348

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