相关论文: The INTEGRAL/IBIS AGN catalogue I: X-ray absorptio…
In this work we have updated the list of AGN detected by INTEGRAL taking into account the new objects listed in the last published INTEGRAL/IBIS survey. We have collected 83 new AGN increasing the number of INTEGRAL detected active galaxies…
In this work the INTEGRAL hard X-ray selected sample of AGN has been used to investigate the possible contribution of absorbing material distributed within the host galaxies to the total amount of NH measured in the X-ray band. We collected…
We report a new sample of obscured active galactic nuclei (AGNs) selected from the XMM serendipitous source and AKARI point-source catalogs. We match X-ray sources with infrared (18 and 90 micron) sources located at |b|>10 deg to create a…
Intrinsic absorption is a fundamental physical property to understand the evolution of active galactic nuclei (AGN). Here a sample of 1290 AGN, selected in the 2-10 keV band from different flux-limited surveys with very high optical…
We develop a new diagnostic method to classify galaxies into AGN hosts, star-forming galaxies, and absorption-dominated galaxies by combining the [O III]/Hbeta ratio with rest-frame U-B color. This can be used to robustly select AGNs in…
The determination of the broad (0.1-100 keV) spectra of active galaxies is crucial for understanding and discriminating among emission models, for estimating the properties of the Comptonising/reflecting region around the central black hole…
For a significant number of the sources detected at high energies (>10 keV) by the INTEGRAL/IBIS and Swift/BAT instruments there is either a lack information about them in the 2-10 keV range or they are totally unidentified. Herein, we…
Aims. We present a 0.2--200 keV broad-band study of absorbed AGN observed with INTEGRAL, XMM-Newton, Chandra and ASCA to investigate the continuum shape and the absorbing/reflecting medium properties. Methods. The sources are selected in…
We study the NH distribution in a complete sample of 88 AGN selected in the 20-40 keV band from INTEGRAL/IBIS observations. We find that the fraction of absorbed (NH > 10^{22} cm^2) sources is 43% while the Compton thick AGN comprise 7% of…
The INTEGRAL mission provides a large data set for studying the hard X-ray properties of AGN and allows testing of the unified scheme for AGN. We present analysis of INTEGRAL IBIS/ISGRI, JEM-X, and OMC data for 199 AGN supposedly detected…
[Abridged]We report on the broadband X-ray properties of a complete sample of absorbed Seyfert galaxies hard X-ray selected with INTEGRAL. The sample is composed of 33 sources: 15 are newly discovered above 20 keV while 18 are already known…
Our goal is to probe the populations of obscured and unobscured AGN investigating their optical-IR and X-ray properties as a function of X-ray flux, luminosity and redshift within a hard X-ray selected sample of 136 X-ray sources in the XMM…
We study the NH distribution in a complete sample of 88 AGN selected in the 20-40 keV band from INTEGRAL/IBIS observations. We find that the fraction of absorbed (NH > 10^22 cm^-2) sources is 43% while Compton thick AGN comprise 7% of the…
In order to investigate the role of absorption in AGN with jets, we have studied the column density distribution of a hard X-ray selected sample of radio galaxies, derived from the INTEGRAL/IBIS and Swift/BAT AGN catalogues (~7-10% of the…
Hard X-ray surveys like those provided by IBIS and BAT on board the INTEGRAL and Swift satellites list a significant number of sources which are unidentified and/or unclassified and which deserve multiwaveband observations to be properly…
We explore the relationship between X-ray absorption and optical obscuration within the BAT AGN Spectroscopic Survey (BASS) which has been collecting and analyzing the optical and X-ray spectra for 641 hard X-ray selected ($E>14$ keV)…
We have combined the CLASXS Chandra survey in Lockman with the Spitzer SWIRE survey data to study the X-ray-infrared connection for AGN. The sample consists of 401 X-ray-sources, of which 306 are detected by Spitzer, and a further 257 AGN…
We use the INTEGRAL all-sky hard X-ray survey to perform a statistical study of a representative sample of nearby AGN. Our entire all-sky sample consists of 127 AGN, of which 91 are confidently detected (>5 sigma) on the time-averaged map…
Analysis of INTEGRAL Core Program and public Open Time observations has recently provided a sample of 60 extragalactic sources selected in the 20-100 keV band above a flux of 1.5 10^-11 erg/cm2/s. As this band probes heavily obscured…
Hard X-ray surveys are an important tool for the study of active galactic nuclei (AGN): they provide almost an unbiased view of absorption in the extragalactic population, allow the study of spectral features such as reflection and high…