Related papers: Testing the starburst/AGN connection with SWIRE X-…
We discuss the spectral analysis of a sample of 63 Active Galactic Nuclei (AGN) detected above a limiting flux of $S(8-24$ keV$)=7\times10^{-14}$ erg/s/cm$^2$ in the multi-tiered NuSTAR Extragalactic Survey program. The sources span a…
In deep X-ray surveys, active galactic nuclei (AGNs) with a broad range of luminosities have been identified. However, cosmologically distant low-luminosity AGN (LLAGN, $L_{\mathrm{X}} \lesssim 10^{42}$ erg s$^{-1}$) identification still…
We combine emission line and X-ray luminosities for 45 sources from the Chandra Deep Field South (CDF-S), and seven HELLAS sources, to obtain a new sample of 52 X-ray selected type-II active galactic nuclei (AGNs). Eighteen of our sources…
Mid-infrared observations are powerful in identifying heavily obscured Active Galactic Nuclei (AGN) which have weak emission in other wavelengths. Data from the Mid-Infrared Instrument (MIRI) onboard JWST provides an excellent opportunity…
As an evolutionary phase of galaxies, active galactic nuclei (AGN) over a large range of redshift have been utilized for understanding cosmic evolution. In particular, the population and evolution of AGNs have been investigated through the…
We present new methods to quantify the AGN population in terms of a multi-dimensional luminosity function that describes the space density of sources as a function of both X-ray and radio luminosity. We compile a sample of 1538 radio and…
The X-ray luminosity function (XLF) of galaxies is dominated by AGN (classified by their optical spectra) above Lx=10**42 erg/s, below this value by normal galaxies. The X-ray flux of AGN at low X-ray luminosity therefore contains…
Searching for active galactic nuclei (AGN) in dwarf galaxies is important for our understanding of the seed black holes that formed in the early Universe. Here, we test infrared selection methods for AGN activity at low galaxy masses. Our…
We searched in the public archive of the Chandra X-ray Observatory as of March 2016 and assembled a sample of 719 galaxies within 50 Mpc with ACIS observations available. By cross-correlation with the optical or near-infrared nuclei of…
We present a catalog of mid-infrared (MIR) spectra of 150 infrared (IR) luminous galaxies in the Spitzer extragalactic first look survey obtained with IRS on board Spitzer. The sample is selected to be brighter than ~0.9 mJy at 24 micron…
We identify sources with extremely hard X-ray spectra (i.e., with photon indices of Gamma<0.6 in the 13 sq. deg. NuSTAR serendipitous survey, to search for the most highly obscured AGNs detected at >10 keV. Eight extreme NuSTAR sources are…
The recent deep X-ray surveys at both soft (0.5--2 keV) and hard (2--10 keV) energies have greatly extended our knowledge of the X-ray source density and spectral shapes at relatively faint fluxes adding further evidence on the fact that…
We present a study of a sample of luminous infrared galaxies (LIGs, L_IR > 10^11 L_sun) observed in the hard (2-10 keV) X rays. The main results are: 1) most LIGs are powered both by AGN and starburst activity; 2) the AGNs in our sample are…
We present a spectroscopically complete sample of 147 infrared-color-selected AGN down to a 22 $\mu$m flux limit of 20 mJy over the $\sim$270 deg$^2$ of the SDSS Stripe 82 region. Most of these sources are in the QSO luminosity regime…
The Swift Gamma-Ray Burst satellite has detected a largely unbiased towards absorption sample of local ($<z> \approx 0.03$) AGN, based solely on their 14--195 keV flux. In the first 9 months of the survey, 153 AGN sources were detected. The…
As part of the "All Wavelength Extended Groth Strip International Survey" (AEGIS), we describe the panchromatic characterization of an X-ray luminous active galactic nucleus (AGN) in a merging galaxy at z=1.15. This object is detected at…
We report the results of identification of 8 hard X-ray sources discovered by the INTEGRAL observatory during the ongoing all-sky survey. These sources have been observed by Chandra. In 6 cases a bright X-ray source was found within the…
We present results from a spectral analysis of a sample of high-redshift (z>3) X-ray selected AGN in the 4 Ms Chandra Deep Field South (CDF-S), the deepest X-ray survey to date. The sample is selected using the most recent spectroscopic and…
The primary X-ray emission in active galactic nuclei (AGN) originates in a compact region called the corona located very close to the super-massive black hole and the accretion disk. The knowledge of the cut-off energy ($E_{cut}$) of the…
Hyper-Luminous Infrared Galaxies (HLIRGs) are the most luminous persistent objects in the Universe. They exhibit extremely high star formation rates, and most of them seem to harbour an AGN. They are unique laboratories to investigate…