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XMM-Newton EPIC and RGS observations of LMC X-3

Kinwah Wu·Roberto Soria·Mathew Page·Irini Sakelliou·Steven Kahn·Cor de Vries
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Abstract

We report the results of preliminary analysis of the XMM_Newton EPIC and RGS observations of the candidate black-hole binary LMC X-3 between February and June 2000. The observations covered both the soft and the hard X-ray spectral states. The hard-state spectra were dominated by a power-law component with a photon index Gamma = 1.9 +/- 0.1. The soft-state spectra consisted of a thermal component with a multi-colour disk temperature T_in = 0.9 keV and a power-law tail with Gamma ~ 2.5--2.7. The model in which the X-rays from LMC X-3 in the high-soft state are powered by a strong stellar wind from a massive companion is not supported by the small line-of-sight absorption (n_H <~ 10^{21} cm^{-2}) deduced from the RGS data. The transition from the soft to the hard state appears to be a continuous process associated with the changes in the mass-transfer rate.

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Kinwah Wu, Roberto Soria, Mathew Page, Irini Sakelliou, Steven Kahn, Cor de Vries. 2000-11-09. XMM-Newton EPIC and RGS observations of LMC X-3. https://doi.org/10.1051/0004-6361%3A20000229

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