EDP Sciences
Free access
Volume 365, Number 1, January I 2001
First Results from XMM-Newton
Page(s) L267 - L272
DOI http://dx.doi.org/10.1051/0004-6361:20000229

A&A 365, L267-L272 (2001)
DOI: 10.1051/0004-6361:20000229

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

K. Wu1,2, R. Soria1, M. J. Page1, I. Sakelliou1, S. M. Kahn3 and C. P. de Vries4.

1  Mullard Space Science Laboratory, University College London, Holmbury St Mary, Dorking, RH5 6NT, UK
2  Research Centre for Theoretical Astrophysics, School of Physics, University of Sydney, NSW 2006, Australia
3  Columbia Astrophysics Laboratory, Columbia University, 550 West 120th Street, New York, NY 10027, USA
4  Space Research Organization of The Netherlands, Sorbonnelaan 2, 3584 CA Utrecht, The Netherlands

(Received 2 October 2000 / Accepted 10 November 2000)

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 $\Gamma \approx1.9$. The soft-state spectra consisted of a thermal component with a multi-colour disk temperature $T_{\rm in}$ of $\sim 0.9$ keV and a power-law tail with $\Gamma \approx 2.7$. 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 ( $n_{\rm H} \simlt 10^{21}$ 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.

Key words: accretion, accretion disks -black hole physics -binaries: general -stars: early type -stars: winds, outflows -X-rays: general

Offprint request: K. Wu

SIMBAD Objects

© ESO 2001