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Results from Monitoring the Broad-Line Radio Galaxy 3C 390.3

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 نشر من قبل Karen Leighly
 تاريخ النشر 1995
  مجال البحث فيزياء
والبحث باللغة English
 تأليف K. M. Leighly




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During 1995, the broad-line radio galaxy 3C 390.3 is the subject of a multi-wavelength monitoring campaign comprised of ROSAT HRI, IUE, and ground based optical, infrared and radio observations. We report preliminary results from the monitoring campaign focusing on the X-ray observations. Snapshot ROSAT observations being made every three days show large amplitude variability. The light curve is dominated by a flare near JD 2449800 characterized by a doubling time scale of 9 days and a general increase in flux after the flare. The optical R and I band light curves show a general increase in flux. The ASCA spectra obtained before and after the flare can be described by an absorbed power law. Spectral variability between the two observations is characterized by an increase in power law index by $DeltaGamma sim 0.08$ at higher flux.

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