Description
We present the results of a new spectroscopic study of Fe K-band absorption in active galactic nuclei (AGN). Using data obtained from the Suzaku public archive we have performed a statistically driven blind search for FeXXV He{alpha} and/or FeXXVI Ly{alpha} absorption lines in a large sample of 51 Type 1.0-1.9 AGN. Through extensive Monte Carlo simulations we find that statistically significant absorption is detected at E>~6.7keV in 20/51 sources at the P_MC_>=95% level, which corresponds to ~40% of the total sample. In all cases, individual absorption lines are detected independently and simultaneously amongst the two (or three) available X-ray imaging spectrometer detectors, which confirms the robustness of the line detections. The most frequently observed outflow phenomenology consists of two discrete absorption troughs corresponding to FeXXV He{alpha} and FeXXVI Ly{alpha} at a common velocity shift. From xstar fitting the mean column density and ionization parameter for the FeK absorption components are log(N_H_/cm^2^)~23 and log({xi}/erg/cm/s)~4.5, respectively. Measured outflow velocities span a continuous range from <1500km/s up to ~100000km/s, with mean and median values of ~0.1c and ~0.056c, respectively. The results of this work are consistent with those recently obtained using XMM-Newton and independently provides strong evidence for the existence of very highly ionized circumnuclear material in a significant fraction of both radio-quiet and radio-loud AGN in the local universe.
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