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SIGMA observations of X-ray Nova Velorum 1993 (GRS 1009-45)

92   0   0.0 ( 0 )
 Added by Paolo Goldoni
 Publication date 1997
  fields Physics
and research's language is English
 Authors P.Goldoni




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We report on hard X-ray observations of X-ray Nova Velorum 1993 (GRS 1009-45) performed with the SIGMA coded mask X-ray telescope in January 1994. The source was clearly detected with a flux of about 60 mCrab in the 40-150 keV energy band during the two observations with a hard spectrum (alpha ~ - 1.9) extending up to ~ 150 keV. These observations confirm the duration of the activity of the source in hard X-rays over 100 days after the first maximum and suggest a spectral hardening which has already been observed in Nova Muscae. These and other characteristics found in these observations strengthen the case for this Nova to be a black hole candidate similar to Nova Muscae.



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