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The X-ray Emission of Quasars as Observed by Ginga

Published online by Cambridge University Press:  19 July 2016

A.J. Lawson  and
M.J.L. Turner
A.J. Lawson
Affiliation:
University of Leicester University Rd. Leicester LE1 7RE United Kingdom
M.J.L. Turner
Affiliation:
University of Leicester University Rd. Leicester LE1 7RE United Kingdom

Abstract

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We present preliminary results on a spectal analysis of quasars observed by the X-ray observatory Ginga. Simple power-law models with fixed Galactic absorbtion provide an adequate description of the spectra for most of the sources in the 2–18 keV band. A small number of sources show evidence for a feature at 6.4 keV (in the source rest frame) due to Fe line emission. Maximum likelihood and Spearman rank tests were used to investigate the relationship between radio loudness and X-ray spectral index in this class of object. These tests showed, respectively, that the mean X-ray spectral index of radio quiet quasars (RQQs) is significantly different from that of flat spectrum radio loud quasars (FRSQs) at the >99% level, and that the dominant relationship with spectral index is radio loudness (not X-ray luminosity or redshift) at >99% significance. This last result has not previously been demonstrated in this band, but agrees with findings in the lower energy Einstein band (0.5–3.5 keV). These results are discussed in the context of current unified models.

Keywords

galaxies: activegalaxies:nucleiquasars:generalradio continuum:galaxiesX-rays:galaxies
Type
Variability
Information
Symposium - International Astronomical Union , Volume 159: Multi-Wavelength Continuum Emission of AGN , 1994 , pp. 123 - 125
Copyright
Copyright © Kluwer 1994 

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