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arXiv · astro-ph/0010546

XMM-Newton Optical Monitor observations of LMC X-3

Roberto Soria·Kinwah Wu·Mathew Page·Irini Sakelliou
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Abstract

We study the optical counterpart of the black-hole X-ray binary LMC X-3, by using XMM-Newton/OM observations carried out during a low-hard X-ray state. We derive a better constraint for the temperature, mass and radius of the companion star, and we show that the star is likely to be a ~ B5 subgiant filling its Roche lobe. Taking into account the effect of X-ray irradiation, we suggest a value f_M = (1.5 +/- 0.3) M_sun for the mass function in this system, lower than previously thought; we provide a more accurate lower limit to the mass of the compact object.

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Roberto Soria, Kinwah Wu, Mathew Page, Irini Sakelliou. 2000-10-26. XMM-Newton Optical Monitor observations of LMC X-3. https://doi.org/10.1051/0004-6361%3A20000065

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