Chandra detection of a parsec scale wind in the Broad Line Radio Galaxy 3C 382

We present unambiguous evidence for a parsec scale wind in the Broad-Line Radio Galaxy (BLRG) 3C 382, the first radio-loud AGN, with $R_{\rm L} = \log_{10}(f_{\rm 5GHz}/f_{4400})>1$, whereby an outflow has been measured with X-ray grating spectroscopy. A 118 ks Chandra grating (HETG) observation of 3C 382 has revealed the presence of several high ionization absorption lines in the soft X-ray band, from Fe, Ne, Mg and Si. The absorption lines are blue-shifted with respect to the systemic velocity of 3C 382 by -840\pm60 km/s and are resolved by Chandra with a velocity width of 340\pm70 km/s. The outflow appears to originate from a single zone of gas of column density $N_{\rm H} = 1.3 \times 10^{21}$ cm$^{-2}$ and ionization parameter $\log \xi = 2.45$. From the above measurements we calculate that the outflow is observed on parsec scales, within the likely range from 10-1000 pc, i.e., consistent with an origin in the Narrow Line Region.Comment: 11 pages, accepted for publication in Astrophysical Journal Letter

Evidence for a circum-nuclear and ionised absorber in the X-ray obscured BroadLine Radio Galaxy 3C 445

Here we present the results of a Suzaku observation of the Broad Line Radio Galaxy 3C 445. We confirm the results obtained with the previous X-ray observations which unveiled the presence of several soft X-ray emission lines and an overall X-ray emission which strongly resembles a typical Seyfert 2 despite of the optical classification as an unobscured AGN. The broad band spectrum allowed us to measure for the first time the amount of reflection (R~0.9) which together with the relatively strong neutral Fe Kalpha emission line (EW ~ 100 eV) strongly supports a scenario where a Compton-thick mirror is present. The primary X-ray continuum is strongly obscured by an absorber with a column density of NH =2-3 x10^{23} cm^{-2}. Two possible scenarios are proposed for the absorber: a neutral partial covering or a mildly ionised absorber with an ionisation parameter log\xi ~ 1.0 erg cm s^{-1}. A comparison with the past and more recent X-ray observations of 3C 445 performed with XMM-Newton and Chandra is presented, which provided tentative evidence that the ionised and outflowing absorber varied. We argue that the absorber is probably associated with an equatorial disk-wind located within the parsec scale molecular torus.Comment: Accepted by MNRAS; 13 pages, 6 figures, 4 table

Arp 299: a second merging system with two active nuclei?

Recent BeppoSAX observations of Arp 299, a powerful far-IR merging starburst system composed of IC 694 and NGC 3690, clearly unveiled for the first time in this system the presence of a strongly absorbed active galactic nucleus (AGN). However the system was not spatially resolved by BeppoSAX. Here we present the analysis of archival Chandra and (for the first time) XMM-Newton observations, which allow us to disentangle the X-ray emission of the two galaxies. The detection of a strong 6.4 keV line in NGC 3690 clearly demonstrates the existence of an AGN in this galaxy, while the presence of a strong 6.7 keV Fe-Kalpha line in the spectrum of IC 694 suggests that also this nucleus might harbor an AGN. This would be the second discovery of two AGNs in a merging system after NGC 6240

Origin of the X-Ray Background and AGN Unification: New Perspectives

We critically review the basic assumptions of the standard model for the synthesis of the XRB in the light of new data from ultradeep surveys by Chandra and XMM, resolving major parts of it. Important constraints come in particular from the observed z-distributions of faint hard X-ray sources -- showing large excesses at redshifts (z~0.8) much lower than expected by the synthesis models -- and from their X/optical/IR SEDs combined with the IR counts of type-II AGNs. Our analysis, although supporting the general scheme which interprets the XRB as due to absorbed AGNs with broad N_H distributions, requires major revision of the other postulate of the XRB synthesis models: the AGN unification. We argue that the unification scheme based on a simple orientation effect fails at high redshifts, where galaxy activity is induced by strong interactions and mergers among gas-rich systems. This helps explaining the observational evidence that type-I and II AGNs follow different evolutionary patterns, with type-I quasars providing a very biased trace of this activity. Combined deep X-ray and IR surveys consistently find that the universe has experienced a violent phase of galaxy activity around z~1, probably related with the assembly of massive galaxies, involving both SF and obscured AGN fueling. Roughly 10 to 20% of this activity has involved substantial AGN emission, this fraction likely reflecting the AGN/starburst duty cycle during the activation phase.Comment: 5 pages, to appear in MNRA

X-ray variability analysis of a large series of XMM-Newton + NuSTAR observations of NGC 3227

We present a series of X-ray variability results from a long XMM-Newton + NuSTAR campaign on the bright, variable AGN NGC 3227. We present an analysis of the lightcurves, showing that the source displays typically softer-when-brighter behaviour, although also undergoes significant spectral hardening during one observation which we interpret as due to an occultation event by a cloud of absorbing gas. We spectrally decompose the data and show that the bulk of the variability is continuum-driven and, through rms variability analysis, strongly enhanced in the soft band. We show that the source largely conforms to linear rms-flux behaviour and we compute X-ray power spectra, detecting moderate evidence for a bend in the power spectrum, consistent with existing scaling relations. Additionally, we compute X-ray Fourier time lags using both the XMM-Newton and - through maximum-likelihood methods - NuSTAR data, revealing a strong low-frequency hard lag and evidence for a soft lag at higher frequencies, which we discuss in terms of reverberation models.Comment: Accepted for publication in MNRAS; 19 pages, 13 figures, 4 tables; minor typographical errors corrected and reference list update

FE K EMISSION AND ABSORPTION FEATURES IN THE XMM-EPIC SPECTRUM OF THE SEYFERT GALAXY IC 4329A

We present a re-analysis of the XMM-Newton long-look of the X-ray bright Seyfert galaxy IC 4329a. The Fe K bandpass is dominated by two peaks, consistent with emission from neutral or near-neutral Fe Ka and KP. A relativistic diskline model whereby both peaks are the result of one doubly-peaked diskline profile is found to be a poor description of the data. Models using two relativistic disklines are found to describe the emission profile well. A low-inclination, moderately-relativistic dual-diskline model is possible if the contribution from narrow components, due to distant material, is small or absent. A high-inclination, moderately relativistic profile for each peak is possible if there are roughly equal contributions from both the broad and narrow components. Upper limits on Fe XXV and Fe XXVI emission and absorption at the systemic velocity of IC 4329a are obtained. We also present the results of RXTE monitoring of this source obtained so far; the combined XMM-Newton and RXTE data sets allow us to explore the time-resolved spectral behavior of this source on time scales ranging from hours to 2 years. We find no strong evidence for variability of the Fe Ka emission line on any time scale probed, likely due to the minimal level of continuum variability. We detect a narrow absorption line, at a energy of 7.68 keV in the rest frame of the source; its significance has been confirmed using Monte Carlo simulations. This feature is most likely due to absorption from Fe XXVI blueshifted to approximately 0.1c relative to the systemic velocity, making IC 4329a the lowest-redshift AGN known with a high-velocity, highly-ionized outflow component. As is often the case with similar outflows seen in high-luminosity quasars, the estimated mass outflow rate is larger than the inflow accretion rate, signaling that the outflow represents a substantial portion of the total energy budget of the AGN. The outflow could arise from a radiatively-driven disk wind, or it may be in the form of a discrete, transient blob of ejected material