A Suzaku survey of Fe K lines in Seyfert 1 AGN. (arXiv:1208.1150v1 [astro-ph.HE])

A Suzaku survey of Fe K lines in Seyfert 1 AGN. (arXiv:1208.1150v1 [astro-ph.HE]):
We construct full broadband models in an analysis of Suzaku observations of
nearby Seyfert 1 AGN (z<0.2) with exposures >50ks and with greater than 30000
counts in order to study their iron line profiles. This results in a sample of
46 objects and 84 observations. After a full modelling of the broadband Suzaku
and Swift-BAT data (0.6-100 keV) we find complex warm absorption is present in
59% of the objects in this sample which has a significant bearing upon the
derived Fe K region parameters. Meanwhile 35% of the 46 objects require some
degree of high column density partial coverer in order to fully model the hard
X-ray spectrum. We also find that a large number of the objects in the sample
(22%) require high velocity, high ionization outflows in the Fe K region
resulting from Fe XXV and Fe XXVI. A further four AGN feature highly ionized Fe
K absorbers consistent with zero outflow velocity, making a total of 14/46
(30%) AGN in this sample showing evidence for statistically significant
absorption in the Fe K region.

Narrow Fe K alpha emission from distant material at 6.4 keV is found to be
almost ubiquitous in these AGN. Examining the 6-7 keV Fe K region we note that
narrow emission lines originating from Fe XXV at 6.63-6.70 keV and from Fe XXVI
at 6.97 keV are present in 52% and 39% of objects respectively.

Our results suggest statistically significant relativistic Fe K alpha
emission is detected in 23 of 46 objects (50%) at >99.5% confidence, measuring
an average emissivity index of q=2.4\pm0.1 and equivalent width EW=96\pm10 eV
using the relline model. When parameterised with a Gaussian we find an average
line energy of 6.32\pm0.04 keV, sigma width=0.470\pm0.05 keV and EW=97\pm19 eV.
Where we can place constraints upon the black hole spin parameter a, we do not
require a maximally spinning black hole in all cases.