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Spectral variability of the nucleus of M33 in a Chandra-ACIS observation

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 نشر من قبل Valentina La Parola
 تاريخ النشر 2002
  مجال البحث فيزياء
والبحث باللغة English
 تأليف V. La Parola




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We have analyzed a 90 ksec long observation of the bright nucleus of M33 made with Chandra/ACIS. We detected low-amplitude (~sim10%) highly significant variability on timescales of ~5000 sec. We also find associated spectral variability. The two main spectral components (a power-law with Gamma~2 and a multicolor disk -MCD- with kT~0.9-1.2 keV) vary in relative flux. The MCD temperature also increases with increasing MCD flux. The pattern of variability is reminiscent of (but not identical to) galactic black hole binaries. A ~5 M$_{odot}$ accreting black hole may explain this source.



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