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Evolution of spectral parameters during a pre-eclipse dip of Her X-1

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 نشر من قبل Beate Stelzer
 تاريخ النشر 1998
  مجال البحث فيزياء
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 تأليف B. Stelzer




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We report on a pre-eclipse dip of the X-ray binary Her X-1 observed by the Rossi X-ray Timing Explorer (RXTE) in July 1996. We present the evolution of the spectral parameters in the 3-18 keV range with a temporal resolution of 16 s and show that the varying flux of the spectrum can be interpreted solely by a time varying column density. We also find that the lightcurve is characterized by symmetric substructures with recurrence time of a few minutes that can be successfully modeled by Gaussian profiles.



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