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On the nature of the microquasar V4641 Sagittarii

S. Chaty·I. F. Mirabel·J. Marti·L. F. Rodriguez
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Abstract

We present photometric and spectroscopic optical and near-infrared (NIR) observations taken during the outburst on September 1999 of the source V4641 Sgr = SAX J1819.3-2525 (in'tzand et al., 2000) = XTE J1819-254 (Markwardt et al., 1999). We show that our observations suggest a distance between 4 and 8 kpc, the spectral type of the companion star being constrained between B3 and A2 V, making the system a High Mass X-ray Binary System (HMXB). In view of the radio and optical/NIR observations, it is possible that the ejecta of the source interacted with the surrounding medium of the source.

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S. Chaty, I. F. Mirabel, J. Marti, L. F. Rodriguez. 2000-11-09. On the nature of the microquasar V4641 Sagittarii. https://arxiv.org/abs/astro-ph/0011192

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