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Variable X-ray Absorption in NGC 4151

Published online by Cambridge University Press:  07 August 2017

R. S. Warwick ,
T. Yaqoob  and
K. A. Pounds
R. S. Warwick
Affiliation:
X-ray Astronomy Group, University of Leicester, Leicester LE1 7RH, United Kingdom
T. Yaqoob
Affiliation:
X-ray Astronomy Group, University of Leicester, Leicester LE1 7RH, United Kingdom
K. A. Pounds
Affiliation:
X-ray Astronomy Group, University of Leicester, Leicester LE1 7RH, United Kingdom

Extract

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The medium energy X-ray spectrum of the Seyfert galaxy NGC 4151 is characterised by a hard power-law continuum, a variable low-energy cut-off and iron line and edge features. Holt et al. (1980) found the spectral form below 4 keV to be incompatible with absorption in a uniform screen of cold gas and interpreted the apparent soft X-ray excess in terms of a partial covering model. However, recent observations point to a somewhat different description of the X-ray absorbing medium present in the nucleus of this galaxy.

Type
Part 3: X-rays and the Central Source
Information
Symposium - International Astronomical Union , Volume 134: Active Galactic Nuclei , 1989 , pp. 182 - 183
Copyright
Copyright © Kluwer 1989 

References

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