We present the second Multi-Epoch X-ray Serendipitous AGN Sample (MEXSAS2), extracted from the 6th release of the XMM Serendipitous Source Catalog (XMMSSC-DR6), cross-matched with Sloan Digital Sky ...Survey quasar Catalogs DR7Q and DR12Q. Our sample also includes the available measurements for masses, bolometric luminosities, and Eddington ratios. Analyses of the ensemble structure function and spectral variability are presented, together with their dependences on such parameters. We confirm a decrease of the structure function with the X-ray luminosity, and find a weak dependence on the black hole mass. We introduce a new spectral variability estimator, taking errors on both fluxes and spectral indices into account. We confirm an ensemble softer when brighter trend, with no dependence of such estimator on black hole mass, Eddington ratio, redshift, X-ray and bolometric luminosity.
Substantial evidence in the last few decades suggests that outflows from supermassive black holes (SMBH) may play a significant role in the evolution of galaxies. These outflows, powered by active ...galactic nuclei (AGN), are thought to be the fundamental mechanism by which the SMBH transfers a significant fraction of its accretion energy to the surrounding environment. Large-scale outflows known as warm absorbers (WA) and fast disk winds known as ultra-fast outflows (UFO) are commonly found in the spectra of many Seyfert galaxies and quasars, and a correlation has been suggested between them. Recent detections of low ionization and low column density outflows, but with a high velocity comparable to UFOs, challenge such initial possible correlations. Observations of UFOs in AGN indicate that their energetics may be enough to have an impact on the interstellar medium (ISM). However, observational evidence of the interaction between the inner high-ionization outflow and the ISM is still missing. We present here the spectral analysis of 12
XMM-Newton
/EPIC archival observations of the quasar PG 1114+445, aimed at studying the complex outflowing nature of its absorbers. Our analysis revealed the presence of three absorbing structures. We find a WA with velocity
v
∼ 530 km s
−1
, ionization log
ξ
/erg cm s
−1
∼ 0.35, and column density log
N
H
/cm
−2
∼ 22, and a UFO with
v
out
∼ 0.145
c
, log
ξ
/erg cm s
−1
∼ 4, and log
N
H
/cm
−2
∼ 23. We also find an additional absorber in the soft X-rays (
E
< 2 keV) with velocity comparable to that of the UFO (
v
out
∼ 0.120
c
), but ionization (log
ξ
/erg cm s
−1
∼ 0.5) and column density (log
N
H
/cm
−2
∼ 21.5) comparable with those of the WA. The ionization, velocity, and variability of the three absorbers indicate an origin in a multiphase and multiscale outflow, consistent with entrainment of the clumpy ISM by an inner UFO moving at ∼15% the speed of light, producing an entrained ultra-fast outflow (E-UFO).
ABSTRACT
A wide-frequency radio study of active galactic nuclei (AGN) is crucial to evaluate the intervening radiative mechanisms responsible for the observed emission and relate them with the ...underlying accretion physics. We present wide-frequency (5–45 GHz), high-sensitivity (few $\mathrm{{\mu }Jy\, beam^{-1}}$), (sub)-kpc Jansky Very Large Array (JVLA) observations of a sample of 30 nearby ($0.003\, \le \, z\, \le \, 0.3$) AGN detected by the International Gamma-Ray Astrophysics Laboratory (INTEGRAL)/Imager on Board the INTEGRAL Satellite (IBIS) at hard X-ray. We find a high detection fraction of radio emission at all frequencies, i.e. ≥95 per cent at 5, 10, and 15 GHz and ≥80 per cent at 22 and 45 GHz. Two sources out of 30 remain undetected at our high sensitivities. The nuclear radio morphology is predominantly compact, sometimes accompanied by extended jet-like structures, or more complex features. The radio spectral energy distributions (SEDs) of the radio cores appear either as single or as a broken power law, a minority of them exhibit a peaked component. The spectral slopes are either flat/inverted or steep, up to a break/peak or over the whole range. The sample mean SED shows a flat slope up to 15 GHz that steepens between 15 and 22 GHz and becomes again flat above 22 GHz. Significant radio–X-ray correlations are observed at all frequencies. About half of the sample features extended emission, clearly resolved by the JVLA, indicating low-power jets or large-scale outflows. The unresolved cores, which often dominate the radio power, may be of jet, outflow, and/or coronal origin, depending on the observed frequency.
Substantial evidence in the last few decades suggests that outflows from supermassive black holes (SMBH) may play a significant role in the evolution of galaxies. These outflows, powered by active ...galactic nuclei (AGN), are thought to be the fundamental mechanism by which the SMBH transfers a significant fraction of its accretion energy to the surrounding environment. Large-scale outflows known as warm absorbers (WA) and fast disk winds known as ultra-fast outflows (UFO) are commonly found in the spectra of many Seyfert galaxies and quasars, and a correlation has been suggested between them. Recent detections of low ionization and low column density outflows, but with a high velocity comparable to UFOs, challenge such initial possible correlations. Observations of UFOs in AGN indicate that their energetics may be enough to have an impact on the interstellar medium (ISM). However, observational evidence of the interaction between the inner high-ionization outflow and the ISM is still missing. We present here the spectral analysis of 12 XMM-Newton/EPIC archival observations of the quasar PG 1114+445, aimed at studying the complex outflowing nature of its absorbers. Our analysis revealed the presence of three absorbing structures. We find a WA with velocity v ∼ 530 km s−1, ionization log ξ/erg cm s−1 ∼ 0.35, and column density log NH/cm−2 ∼ 22, and a UFO with vout ∼ 0.145c, log ξ/erg cm s−1 ∼ 4, and log NH/cm−2 ∼ 23. We also find an additional absorber in the soft X-rays (E < 2 keV) with velocity comparable to that of the UFO (vout ∼ 0.120c), but ionization (log ξ/erg cm s−1 ∼ 0.5) and column density (log NH/cm−2 ∼ 21.5) comparable with those of the WA. The ionization, velocity, and variability of the three absorbers indicate an origin in a multiphase and multiscale outflow, consistent with entrainment of the clumpy ISM by an inner UFO moving at ∼15% the speed of light, producing an entrained ultra-fast outflow (E-UFO).
We report the details of an XMM-Newton observation of the cluster of galaxies Zw 1305.4+2941 at the intermediate redshift z = 0.241, increasing the small number of Interesting X-ray constraints on ...properties of similar to 3 keV systems above z = 0.1. Based on the similar to 45 ks XMM-Newton observation, we find that within a radius of 228 kpc the cluster has an unabsorbed X-ray flux of fx = (2.07 plus or minus 0.06) x 10 super(-18) ergs cm super(-2) s super(-1) temperature of kT = 3.17 plus or minus 0.19 keV, in good agreement with the previous ROSAT determination, and an abundance of 0.93 super(+) sub(-) super(0) sub(0) super(.) sub(.) super(2) sub(2) super(4) sub(9) Z unk. Within r sub(500) = 723 plus or minus 10 kpc the rest-frame bolometric X-ray luminosity is Lx (r sub(500)) = (1.25 plus or minus 0.16) x 10 super(44) h super(-) sub(7) super(2) sub(0) ergs s super(-1). The cluster obeys the scaling relations for Lx, T, and the velocity dispersion unk derived at intermediate redshift for kT unk 4 keV, for which we provide new fits for all objects in the literature. The mass derived from an isothermal NFW model fit is M sub(vlr) unk (2.77 plus or minus 0.21) x 10 super(14) M unk, with the concentration parameter e = 7.9 plus or minus 0.5.
We investigate the dichotomy between jetted and non-jetted Active Galactic Nuclei (AGNs), focusing on the fundamental differences of these two classes in the accretion physics onto the central ...supermassive black hole (SMBH). Our aim is to study and constrain the structure, kinematics and physical state of the nuclear environment in the Broad Line Radio Galaxy (BLRG) PKS 2251+11. The high X-ray luminosity and the relative proximity make such AGN an ideal candidate for a detailed analysis of the accretion regions in radio galaxies. We performed a spectral and timing analysis of a \(\sim\)64 ks observation of PKS 2251+11 in the X-ray band with XMM-Newton. We modeled the spectrum considering an absorbed power law superimposed to a reflection component. We performed a time-resolved spectral analysis to search for variability of the X-ray flux and of the individual spectral components. We found that the power law has a photon index \(\Gamma=1.8\pm 0.1\), absorbed by an ionized partial covering medium with a column density \(N_H=(10.1\pm 0.8) \times 10^{23}\) cm\(^{-2}\), a ionization parameter \(\log{\xi}=1.3\pm 0.1\) erg s\(^{-1}\) cm and a covering factor \(f\simeq90\%\). Considering a density of the absorber typical of the Broad Line Region (BLR), its distance from the central SMBH is of the order of \(r\sim 0.1\) pc. An Fe K\(\alpha\) emission line is found at 6.4 keV, whose intensity shows variability on time scales of hours. We derived that the reflecting material is located at a distance \(r\gtrsim600r_s\), where \(r_s\) is the Schwarzschild radius. Concerning the X-ray properties, we found that PKS 2251+11 does not differ significantly from the non-jetted AGNs, confirming the validity of the unified model in describing the inner regions around the central SMBH, but the lack of information regarding the state of the very innermost disk and SMBH spin still leave unconstrained the origin of the jet.
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