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

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 نشر من قبل Peter Kretschmar
 تاريخ النشر 2004
  مجال البحث فيزياء
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 تأليف P. Kretschmar




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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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