R Udiger Staubert and Michael Maisack
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چکیده
We report the detection of the bright radio quiet quasar PG 1416-129 by the OSSE instrument on the Compton Gamma Ray Observatory (CGRO). This object had the hardest spectral index of all known AGN in the energy range 2-20 keV ((= 1:1 0:1) when observed by Ginga. We nd that the source is variable at energies > 50 keV during the OSSE observation, and that the OSSE spectrum is steeper than the Ginga spectrum. The broad-band X-ray spectrum resembles that of Seyfert galaxies, supporting models which interpret radio quiet quasars as the high-luminosity counterparts of Seyferts.
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