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ASCA observation of Unusually X-ray Hard Radio Quiet QSO Kaz 102

Takamitsu Miyaji·Yoshitaka Ishisaki·Yoshihiro Ueda·Yasushi Ogasaka·Hisamitsu Awaki·Kiyoshi Hayashida
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Abstract

We have observed a radio-quiet QSO Kaz 102 (z=0.136) with ASCA as a part of our program of complete spectral characterization of hard X-ray selected AGNs. We found that Kaz 102 shows unusual spectral properties. A simple power-law with absorption in our galaxy gave a satisfactory description of the spectrum. However, it showed a very hard photon index of Gamma=1.0 with no sign of deep absorption or a prominent spectral feature. We further explored the Compton reflection with Fe K-alpha line and warm absorber models for hardening the spectrum. Both gave statistically satisfactory fits. However, the Compton reflection model requires a very low metal abundance (0.03-0.07 in solar units).The warm absorber model with no direct component is preferred and gave a very high ionization parameter xi=200. If this is the case, the values of xi, warm absorber column density, and variability over about 10 years may suggest that the warm absorber resides in the broad-line region and crosses the line of sight to the central X-ray source.

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Takamitsu Miyaji, Yoshitaka Ishisaki, Yoshihiro Ueda, Yasushi Ogasaka, Hisamitsu Awaki, Kiyoshi Hayashida. 2003-02-20. ASCA observation of Unusually X-ray Hard Radio Quiet QSO Kaz 102. https://doi.org/10.1093/pasj%2F55.2.l11

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