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Near-infrared identification of the counterpart to X1908+075: a new OB-supergiant X-ray binary

Thierry Morel·Yves Grosdidier
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Abstract

We report the near-infrared (IR) identification of the likely counterpart to X1908+075, a highly-absorbed Galactic X-ray source recently suspected to belong to the rare class of OB supergiant-neutron star binary systems. Our JHKs-band imaging of the field reveals the existence within the X-ray error boxes of a near-IR source consistent with an early-type star lying at d=7 kpc and suffering A(V)=16 mag of extinction, the latter value being in good agreement with the hydrogen column density derived from a modelling of the X-ray spectrum. Our follow-up, near-IR spectroscopic observations confirm the nature of this candidate and lead to a late O-type supergiant classification, thereby supporting the identification of a new Galactic OB-supergiant X-ray binary.

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Thierry Morel, Yves Grosdidier. 2004-10-07. Near-infrared identification of the counterpart to X1908+075: a new OB-supergiant X-ray binary. https://doi.org/10.1111/j.1365-2966.2004.08488.x

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