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The ASCA X-ray spectrum of the powerful radio galaxy 3C109

S. W. Allen·A. C. Fabian·E. Idesawa·H. Inoue·T. Kii·C. Otani
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Abstract

We report the results from an ASCA X-ray observation of the powerful Broad Line Radio Galaxy, 3C109. The ASCA spectra confirm our earlier ROSAT detection of intrinsic X-ray absorption associated with the source. The absorbing material obscures a central engine of quasar-like luminosity. The luminosity is variable, having dropped by a factor of two since the ROSAT observations 4 years before. The ASCA data also provide evidence for a broad iron emission line from the source, with an intrinsic FWHM of ~ 120,000 km/s. Interpreting the line as fluorescent emission from the inner parts of an accretion disk, we can constrain the inclination of the disk to be $> 35$ degree, and the inner radius of the disk to be $< 70$ Schwarzschild radii. Our results support unified schemes for active galaxies, and demonstrate a remarkable similarity between the X-ray properties of this powerful radio source, and those of lower luminosity, Seyfert 1 galaxies.

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S. W. Allen, A. C. Fabian, E. Idesawa, H. Inoue, T. Kii, C. Otani. 1997-01-08. The ASCA X-ray spectrum of the powerful radio galaxy 3C109. https://doi.org/10.1093/mnras%2F286.3.765

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