Suzaku observations of 'bare' active galactic nuclei. (arXiv:1210.4593v1 [astro-ph.HE])

Suzaku observations of 'bare' active galactic nuclei. (arXiv:1210.4593v1 [astro-ph.HE]):
We present a X-ray spectral analysis of a large sample of 25 'bare' active
galactic nuclei, sources with little or no complicating intrinsic absorption,
observed with Suzaku. Our work focuses on studying the potential contribution
from relativistic disc reflection, and examining the implications of this
interpretation for the intrinsic spectral complexities frequently displayed by
AGN in the X-ray bandpass. During the analysis, we take the unique approach of
attempting to simultaneously undertake a systematic analysis of the whole
sample, as well as a detailed treatment of each individual source, and find
that disc reflection has the required flexibility to successfully reproduce the
broadband spectrum observed for all of the sources considered. Where possible,
we use the reflected emission to place constraints on the black hole spin for
this sample of sources. Our analysis suggests a general preference for rapidly
rotating black holes, which if taken at face value is most consistent with the
scenario in which SMBH growth is dominated by prolonged, ordered accretion.
However, there may be observational biases towards AGN with high spin in the
compiled sample, limiting our ability to draw strong conclusions for the
general population at this stage. Finally, contrary to popular belief, our
analysis also implies that the dichotomy between radio loud/radio quiet AGN is
not solely related to black hole spin.