- ID:
- ivo://CDS.VizieR/J/ApJ/857/27
- Title:
- A catalog of post-starburst QSOs from SDSS-DR7Q
- Short Name:
- J/ApJ/857/27
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalog of nearby (z<=0.5) quasars with significant features of post-starburst stellar populations in their optical spectra: so-called post-starburst quasars, or PSQs. After carefully decomposing spectra from the Sloan Digital Sky Survey (SDSS) Data Release 7 (DR7) Quasar Catalog into quasar and host-galaxy components, we derive a sample of 208 PSQs. Their host-galaxy components have strong H{delta} absorption (EW>=6{AA}) indicating a significant contribution of an intermediate-aged stellar population formed in a burst of star formation within the past 1Gyr, which makes them potentially useful for studying the co-evolution of supermassive black holes and their host galaxies.
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- ID:
- ivo://CDS.VizieR/J/other/ChA+A/32.351
- Title:
- Accretion rate distributions of AGNs
- Short Name:
- J/other/ChA+A/32
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The redshift, central black hole mass and accretion rate are important parameters when studying the AGN evolution. The central black hole masses for 172 quasars and Seyfert galaxies are calculated in this paper using the reverberation mapping method. The distributions of central black hole masses, redshifts and the Eddington accretion rates are analyzed, to verify the transition from the quasar to the Seyfert galaxy in the course of evolution.
- ID:
- ivo://CDS.VizieR/J/A+AS/147/169
- Title:
- Accurate positions of 2978 SBS objects
- Short Name:
- J/A+AS/147/169
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Optical positions of 2978 objects listed in the Second Byurakan Survey (SBS) were obtained using the Digitized Sky Survey (DSS), and are given with an rms un certainty ~1 arcsec in each coordinate.
- ID:
- ivo://CDS.VizieR/J/ApJS/200/8
- Title:
- AGES: the AGN and Galaxy Evolution Survey
- Short Name:
- J/ApJS/200/8
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The AGN and Galaxy Evolution Survey (AGES) is a redshift survey covering, in its standard fields, 7.7deg^2^ of the Bootes field of the NOAO Deep Wide-Field Survey. The final sample consists of 23745 redshifts. There are well-defined galaxy samples in 10 bands (the B_W_, R, I, J, K, IRAC 3.6, 4.5, 5.8, and 8.0um, and MIPS 24um bands) to a limiting magnitude of I<20mag for spectroscopy. For these galaxies, we obtained 18163 redshifts from a sample of 35200 galaxies, where random sparse sampling was used to define statistically complete sub-samples in all 10 photometric bands. The median galaxy redshift is 0.31, and 90% of the redshifts are in the range 0.085<z<0.66. Active galactic nuclei (AGNs) were selected as radio, X-ray, IRAC mid-IR, and MIPS 24um sources to fainter limiting magnitudes (I<22.5mag for point sources). Redshifts were obtained for 4764 quasars and galaxies with AGN signatures, with 2926, 1718, 605, 119, and 13 above redshifts of 0.5, 1, 2, 3, and 4, respectively. We detail all the AGES selection procedures and present the complete spectroscopic redshift catalogs and spectral energy distribution decompositions. Photometric redshift estimates are provided for all sources in the AGES samples.
- ID:
- ivo://CDS.VizieR/J/MNRAS/405/2062
- Title:
- AGN candidates from 2MASS/ROSAT catalogs
- Short Name:
- J/MNRAS/405/2062
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report on the near-infrared-selected active galactic nuclei (AGN) candidates extracted from Two Micron All Sky Survey (2MASS)/ROSAT catalogues and discuss their properties. First, near-infrared counterparts of an X-ray source in ROSAT catalogues [namely bright source catalogue (BSC, Cat. IX/10) and faint source catalogue (FSC, Cat. IX/29)] were extracted by positional cross-identification of <=30arcsec. As these counterparts would contain many mis-identifications, we further imposed near-infrared colour selection criteria and extracted reliable AGN candidates (BSC: 5273, FSC: 10071). Of the 5273 (10071) candidates in the BSC (FSC), 2053 (1008) are known AGNs. Near-infrared and X-ray properties of candidates show similar properties with known AGNs and are consistent with the previous studies. We also searched for counterparts in other wavelengths (i.e. optical, near-infrared and radio) and investigated properties in multiwavelength. No significant difference between known AGNs and unclassified sources could be seen. However, some unclassified sources in the FSC showed slightly different properties compared with known AGNs. Consequently, it is highly probable that we could extract reliable AGN candidates, though candidates in the FSC might be spurious.
- ID:
- ivo://CDS.VizieR/J/ApJS/172/383
- Title:
- AGN candidates in the COSMOS field
- Short Name:
- J/ApJS/172/383
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present spectroscopic redshifts for the first 466 X-ray and radio-selected AGN targets in the 2deg^2^ COSMOS field. Spectra were obtained with the IMACS instrument on the Magellan (Baade) telescope, using the nod-and-shuffle technique. We identify a variety of type 1 and type 2 AGNs, as well as red galaxies with no emission lines. Our redshift yield is 72% down to i_AB_=24, although the yield is >90% for i_AB_<22. We expect the completeness to increase as the survey continues. When our survey is complete and additional redshifts from the zCOSMOS project are included, we anticipate ~1100 AGNs with redshifts over the entire COSMOS field. Our redshift survey is consistent with an obscured AGN population that peaks at z~0.7, although further work is necessary to disentangle the selection effects.
7. AGN feedback
- ID:
- ivo://CDS.VizieR/J/MNRAS/471/28
- Title:
- AGN feedback
- Short Name:
- J/MNRAS/471/28
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Several studies support the existence of a link between the active galactic nucleus (AGN) and star formation activity. Radio jets have been argued to be an ideal mechanism for direct interaction between the AGN and the host galaxy. A drawback of previous surveys of AGN is that they are fundamentally limited by the degeneracy between redshift and luminosity in flux-density limited samples. To overcome this limitation, we present far-infrared Herschel observations of 74 radio-loud quasars (RLQs), 72 radio-quiet quasars (RQQs) and 27 radio galaxies (RGs), selected at 0.9<z<1.1, which span over two decades in optical luminosity. By decoupling luminosity from evolutionary effects, we investigate how the star formation rate (SFR) depends on AGN luminosity, radio-loudness and orientation. We find that (1) the SFR shows a weak correlation with the bolometric luminosity for all AGN sub-samples, (2) the RLQs show an SFR excess of about a factor of 1.4 compared to the RQQs, matched in terms of black hole mass and bolometric luminosity, suggesting that either positive radio-jet feedback or radio AGN triggering is linked to star formation triggering, and (3) RGs have lower SFRs by a factor of 2.5 than the RLQ sub-sample with the same BH mass and bolometric luminosity. We suggest that there is some jet power threshold at which radio-jet feedback switches from enhancing star formation (by compressing gas) to suppressing it (by ejecting gas). This threshold depends on both galaxy mass and jet power.
- ID:
- ivo://CDS.VizieR/J/A+A/562/A21
- Title:
- AGN feedback from CO observations
- Short Name:
- J/A+A/562/A21
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We study the properties of massive, galactic-scale outflows of molecular gas and investigate their impact on galaxy evolution. We present new IRAM PdBI CO(1-0) observations of local ULIRGs and QSO hosts: clear signature of massive and energetic molecular outflows, extending on kpc scales, is found in the CO(1-0) kinematics of four out of seven sources, with measured outflow rates of several 100M_{sun}_/yr. We combine these new observations with data from the literature, and explore the nature and origin of massive molecular outflows within an extended sample of 19 local galaxies.
- ID:
- ivo://CDS.VizieR/J/A+A/535/A69
- Title:
- AGN Fermi/LAT {gamma}-ray and 37GHz fluxes
- Short Name:
- J/A+A/535/A69
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Although the Fermi mission has increased our knowledge of {gamma}-ray AGN, many questions remain, such as the site of {gamma}-ray production, the emission mechanism, and the factors that govern the strength of the emission. Using data from a high radio band, 37GHz, uncontaminated by other radiation components besides the jet emission, we study these questions with averaged flux densities over the the first year of Fermi operations. We look for possible correlations between the 100MeV-100GeV band used by the Fermi satellite and 37GHz radio band observed at the Aalto University Metsahovi Radio Telescope, as well as for differences between the {gamma}-ray emission of different AGN subsamples. We use data averaged over the 1FGL period. Our sample includes 249 northern AGN, including a complete sample of 68 northern AGN with a measured average flux density exceeding 1Jy.
- ID:
- ivo://CDS.VizieR/J/AJ/130/1418
- Title:
- AGN jet kinematics
- Short Name:
- J/AJ/130/1418
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present total and polarized intensity images of 15 active galactic nuclei obtained with the Very Long Baseline Array at 7mm (43GHz) wavelength at 17 epochs from 1998 March to 2001 April. At some epochs the images are accompanied by nearly simultaneous polarization measurements at 3mm (86GHz) with the Berkeley-Illinois-Maryland Association (BIMA) array (Hat Creek, California), 1.35/0.85mm (230/350GHz) with the James Clerk Maxwell Telescope (JCMT; using SCUBA and its polarimeter, and at the Steward Observatory 1.5m telescope (Mount Lemmon, Arizona) with the Two-Holer Polarimeter/Photometer over an effective wavelength range of ~6000-7000{AA}. Here we analyze the 7mm images to define the properties of the jets of two radio galaxies, five BL Lac objects, and eight quasars on angular scales >~0.1mas. We determine the apparent velocities of 106 features in the jets.