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Spectral and temporal properties of X-ray emission from the ultra-luminous source X-9 in M81

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 نشر من قبل Valentina La Parola
 تاريخ النشر 2001
  مجال البحث فيزياء
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 تأليف V.La Parola




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We have analysed the spectra and the variability of individual X-ray sources in the M-81 field using data from the available ROSAT-PSPC and ROSAT-HRI observations of this nearby spiral galaxy. Here we present the results on the second brightest source in the field (X-9 - Fabbiano, 1988 ApJ 325 544), whose identification and interpretation is still unclear. Our work includes the study of the shape of X-9 from HRI data, the light curve and hardness ratio evolution, and the spectral analysis.



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