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XMM-Newton Observations of the Be/X-ray transient A0538-66 in quiescence

P. Kretschmar·J. Wilms·R. Staubert·I. Kreykenbohm·W. A. Heindl
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Abstract

We present XMM-Newton observations of the recurrent Be/X-ray transient A0538-66, situated in the Large Magellanic Cloud, in the quiescent state. Despite a very low luminosity state of (5-8)E33 ergs/s in the range 0.3-10 keV, the source is clearly detected up to ~8 keV. and can be fitted using either a power law with photon index alpha=1.9+-0.3 or a bremsstrahlung spectrum with kT=3.9+3.9-1.7 keV. The spectral analysis confirms that the off-state spectrum is hard without requiring any soft component, contrary to the majority of neutron stars observed in quiescence up to now.

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P. Kretschmar, J. Wilms, R. Staubert, I. Kreykenbohm, W. A. Heindl. 2004-06-01. XMM-Newton Observations of the Be/X-ray transient A0538-66 in quiescence. https://arxiv.org/abs/astro-ph/0406015

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