- ID:
- ivo://CDS.VizieR/J/A+A/577/A121
- Title:
- The XMM-ATLAS catalogues
- Short Name:
- J/A+A/577/A121
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Wide area X-ray and far infrared surveys are a fundamental tool to investigate the link between AGN growth and star formation, especially in the low-redshift universe (z<1). The Herschel Terahertz Large Area survey (H-ATLAS) has covered 550deg^2^ in five far-infrared and sub-mm bands, 16deg^2^ of which have been presented in the Science Demonstration Phase (SDP) catalogue. Here we introduce the XMM-Newton observations in H-ATLAS SDP area, covering 7.1deg^2^ with flux limits of 2*10^-15^, 6*10^-15^, and 9*10^-15^erg/s/cm^2^ in the 0.5-2, 0.5-8 and 2-8keV bands, respectively. We present the source detection and the catalogue, which includes 1700, 1582 and 814 sources detected by emldetect in the 0.5-8, 0.5-2 and 2-8keV bands, respectively; the number of unique sources is 1816. We extract spectra and derive fluxes from power-law fits for 398 sources with more than 40 counts in the 0.5-8keV band. We compare the best-fit fluxes with the catalogue ones, obtained by assuming a common photon index of Gamma=1.7; we find no bulk difference between the fluxes, and a moderate dispersion of s=0.33dex. Using wherever possible the fluxes from the spectral fits, we derive the 2-10keV Log N-Log S, which is consistent with a Euclidean distribution. Finally, we release computer code for the tools developed for this project.
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- ID:
- ivo://CDS.VizieR/J/A+A/555/A42
- Title:
- The XMM-CDFS catalogues
- Short Name:
- J/A+A/555/A42
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Nuclear obscuration plays a key role in the initial phases of AGN growth, yet not many highly obscured AGN are currently known beyond the local Universe, and their search is an active topic of research. The XMM-Newton survey in the Chandra Deep Field South (XMM-CDFS) aims at detecting and studying the spectral properties of a significant number of obscured and Compton-thick (NH=10^24^cm^-2^ ) AGN. The large effective area of XMM-Newton in the 2-10 and 5-10keV bands, coupled with a 3.45Ms nominal exposure time (2.82 and 2.45Ms after lightcurve cleaning for MOS and PN respectively), allows us to build clean samples in both bands, and makes the XMM-CDFS the deepest XMM-Newton survey currently published in the 5-10keV band. The large multi- wavelength and spectroscopic coverage of the CDFS area allows for an immediate and abundant scientific return. In this paper, we present the data reduction of the XMM-CDFS observations, the method for source detection in the 2-10 and 5-10keV bands, and the resulting catalogues. A number of 339 and 137 sources are listed in the above bands with flux limits of 6.6x10^-16^ and 9.5x10^-16^erg/s/cm^2^, respectively. The flux limits at 50% of the maximum sky coverage are 1.8x10^-15^ and 4.0x10^-15^erg/s/cm^2^, respectively. The catalogues have been cross-correlated with the Chandra ones: 315 and 130 identifications have been found with a likelihood- ratio method, respectively. A number of 15 new sources, previously undetected by Chandra, is found; 5 of them lie in the 4Ms area. Redshifts, either spectroscopic or photometric, are available for ~92% of the sources. The number counts in both bands are presented and compared to other works. The survey coverage has been calculated with the help of two extensive sets of simulations, one set per band. The simulations have been produced with a newly-developed simulator, written with the aim of the most careful reproduction of the background spatial properties. For this reason, we present a detailed decomposition of the XMM-Newton background into its components: cosmic, particle, and residual soft protons. The three components have different spatial distributions. The importance of these three components depends on the band and on the camera; the particle background is the most important one (80-90% of the background counts), followed by the soft protons (4-20%).
- ID:
- ivo://CDS.VizieR/J/ApJ/810/14
- Title:
- Third catalog of LAT-detected AGNs (3LAC)
- Short Name:
- J/ApJ/810/14
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The third catalog of active galactic nuclei (AGNs) detected by the Fermi-LAT (3LAC) is presented. It is based on the third Fermi-LAT catalog (3FGL) of sources detected between 100MeV and 300GeV with a Test Statistic greater than 25, between 2008 August 4 and 2012 July 31. The 3LAC includes 1591 AGNs located at high Galactic latitudes (|b|>10{deg}), a 71% increase over the second catalog based on 2 years of data. There are 28 duplicate associations, thus 1563 of the 2192 high-latitude gamma-ray sources of the 3FGL catalog are AGNs. Most of them (98%) are blazars. About half of the newly detected blazars are of unknown type, i.e., they lack spectroscopic information of sufficient quality to determine the strength of their emission lines. Based on their gamma-ray spectral properties, these sources are evenly split between flat-spectrum radio quasars (FSRQs) and BL Lacs. The most abundant detected BL Lacs are of the high-synchrotron-peaked (HSP) type. About 50% of the BL Lacs have no measured redshifts. A few new rare outliers (HSP-FSRQs and high-luminosity HSP BL Lacs) are reported. The general properties of the 3LAC sample confirm previous findings from earlier catalogs. The fraction of 3LAC blazars in the total population of blazars listed in BZCAT remains non-negligible even at the faint ends of the BZCAT-blazar radio, optical, and X-ray flux distributions, which hints that even the faintest known blazars could eventually shine in gamma-rays at LAT-detection levels. The energy-flux distributions of the different blazar populations are in good agreement with extrapolation from earlier catalogs.
- ID:
- ivo://CDS.VizieR/J/A+AS/143/357
- Title:
- Tuorla Quasar Monitoring
- Short Name:
- J/A+AS/143/357
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The observations presented in table 3 were made by using the 1.03m Dall-Kirkham-type telescope (f/8.45) of Tuorla Observatory with a SBIG ST-8 CCD-camera and a standard V-band filter. Table 4 includes data (B-, V- , and R-bands) observed at the Nordic Optical Telescope (NOT) on La Palma. Corrections for dark-current effects, additive effects (bias) and multiplicative effects (flatfield) were applied. Due to the relatively small field of view of the telescope separate frames of comparison stars were exposed for Mrk 421 and 4C 29.45. For the other objects normal differential photometry methods were applied. Exposure times with the Tuorla 1.03 meter telescope were between 60 and 240 seconds for objects brighter than 16 mag. For fainter objects, we have combined several exposures to achieve a sufficiently high signal to noise ratio.
- ID:
- ivo://CDS.VizieR/J/MNRAS/426/2703
- Title:
- Type 1 AGN at low z. II.
- Short Name:
- J/MNRAS/426/2703
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We explore the relative strength of the narrow emission lines in a Sloan Digital Sky Survey based sample of broad H{alpha} selected active galactic nuclei (AGN), defined in Paper I (Stern & Laor, 2010, Cat. J/MNRAS/423/600).
- ID:
- ivo://CDS.VizieR/J/A+A/534/A110
- Title:
- Type-2 AGN from XMM-COSMOS bolometric output
- Short Name:
- J/A+A/534/A110
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Study of the multi-wavelength properties of a sample of 255 spectroscopically identified X-ray selected Type-2 AGN from the XMM-COSMOS survey. For each source, X-ray ID, spectroscopic redshift, logarithm of the 2-10keV luminosity, logarithm of the bolometric luminosity, bolometric correction, logarithm of the stellar mass, star formation rate, absolute magnitude M_U_, absolute magnitude M_V_, absolute magnitude M_J_ (Johnson-Kron-Cousin system), morphological class.
- ID:
- ivo://CDS.VizieR/J/MNRAS/423/600
- Title:
- Type-1 low-z AGN emission properties
- Short Name:
- J/MNRAS/423/600
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We analyze the emission properties of a new sample of 3,579 type 1 AGN, selected from the SDSS DR7 based on the detection of broad H-{alpha} emission. The sample extends over a broad H-{alpha} luminosity L_bHa_ of 10^40^-10^44^erg/s and a broad H-{alpha} FWHM of 1,000-25,000km/s, which covers the range of black hole mass 10^6^<M_BH_/M{sun}<10^9.5^ and luminosity in Eddington units 10^-3^<L/L_Edd_<1. We combine ROSAT, GALEX and 2MASS observations to form the SED from 2.2um to 2keV. We find the following: 1. The distribution of the H-{alpha} FWHM values is independent of luminosity. 2. The observed mean optical-UV SED is well matched by a fixed shape SED of luminous quasars, which scales linearly with L_bHa_, and a host galaxy contribution. 3. The host galaxy r-band (fibre) luminosity function follows well the luminosity function of inactive non-emission line galaxies (NEG), consistent with a fixed fraction of ~3% of NEG hosting an AGN, regardless of the host luminosity. 4. The hosts of lower luminosity AGN have a mean z band luminosity and u-z colour which are identical to NEG with the same redshift distribution. With increasing L_bHa_ the AGN hosts become bluer and less luminous than NEG. The implied increasing star formation rate with L_bHa_ is consistent with the relation for SDSS type 2 AGN of similar bolometric luminosity. 5. The optical-UV SED of the more luminous AGN shows a small dispersion, consistent with dust reddening of a blue SED, as expected for thermal thin accretion disc emission. 6. There is a rather tight relation of {nu}L_{nu}_(2keV) and L_bHa_, which provides a useful probe for unobscured (true) type 2 AGN. 7. The primary parameter which drives the X-ray to UV emission ratio is the luminosity, rather than M_BH_ or L/L_Edd_.
- ID:
- ivo://CDS.VizieR/J/A+A/535/A80
- Title:
- Type-2 QSOs in XMM-COSMOS
- Short Name:
- J/A+A/535/A80
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We explore the connection between black hole growth at the center of obscured quasars selected from the XMM-COSMOS survey and the physical properties of their host galaxies. We study a bolometric regime (<Lbol>=8x10^45^erg/s) where several theoretical models invoke major galaxy mergers as the main fueling channel for black hole accretion. To derive robust estimates of the host galaxy properties, we use an SED fitting technique to distinguish the AGN and host galaxy emission. We evaluate the effect on galaxy properties estimates of being unable to remove the nuclear emission from the SED. The superb multi-wavelength coverage of the COSMOS field allows us to obtain reliable estimates of the total stellar masses and star formation rates (SFRs) of the hosts. We supplement this information with a morphological analysis of the ACS/HST images, optical spectroscopy, and an X-ray spectral analysis.
- ID:
- ivo://CDS.VizieR/J/AJ/136/2373
- Title:
- Type 2 quasars from SDSS
- Short Name:
- J/AJ/136/2373
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Type 2 quasars are luminous active galactic nuclei whose central regions are obscured by large amounts of gas and dust. In this paper, we present a catalog of type 2 quasars from the Sloan Digital Sky Survey, selected based on their optical emission lines. The catalog contains 887 objects with redshifts z<0.83; this is 6 times larger than the previous version and is by far the largest sample of type 2 quasars in the literature.
- ID:
- ivo://CDS.VizieR/J/ApJ/878/11
- Title:
- Type 1 vs 2 X-ray-selected COSMOS AGNs & environment
- Short Name:
- J/ApJ/878/11
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The unified model of active galactic nuclei (AGNs) proposes that different AGN optical spectral types are caused by different viewing angles with respect to an obscuring "torus". Therefore, this model predicts that type 1 and type 2 AGNs should have similar host-galaxy properties. We investigate this prediction with 2463 X-ray-selected AGNs in the COSMOS field. We divide our sample into type 1 and type 2 AGNs based on their spectra, morphologies, and variability. We derive their host-galaxy stellar masses (M_*_) through spectral energy distribution (SED) fitting, and we find that the hosts M_*_ of type 1 AGNs tend to be slightly smaller than those of type 2 AGNs by {Delta}logM_*_~0.2dex (~4{sigma} significance). Besides deriving star formation rates (SFRs) from SED fitting, we also utilize far-infrared (FIR) photometry and a stacking method to obtain FIR-based SFRs. We find that the SFRs of type 1 and type 2 sources are similar once their redshifts and X-ray luminosities are controlled. We also investigate the cosmic environment, and we find that the surface number densities (sub-Mpc) and cosmic-web environments (~1-10Mpc) are similar for both populations. In summary, our analyses show that the host galaxies of type 1 and type 2 AGNs have similar SFRs and cosmic environments in general, but the former tend to have a lower M_*_ than the latter. The difference in M_*_ indicates that the AGN unification model is not strictly correct, and both host galaxy and torus may contribute to the optical obscuration of AGNs.
