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31. AGN feedback from CO observations
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.
32. AGN Fermi/LAT {gamma}-ray and 37GHz fluxes
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.
33. AGN from the RASS
ID:
ivo://CDS.VizieR/J/A+AS/110/469
Title:
AGN from the RASS
Short Name:
J/A+AS/110/469
Date:
21 Oct 2021
Publisher:
CDS
Description:
This paper presents long slit CCD spectroscopy and X-ray data of 283 AGN detected in the ROSAT-All Sky Survey (RASS). Basis of the sample is the pre-identification of 4651 RASS sources on 134 sky fields (covering in total ~3500sq.deg.). The 283 presented AGN were selected from 1253 AGN candidates resulting from the pre-identification work.
34. AGN global star-forming properties
ID:
ivo://CDS.VizieR/J/MNRAS/466/3161
Title:
AGN global star-forming properties
Short Name:
J/MNRAS/466/3161
Date:
21 Oct 2021
Publisher:
CDS
Description:
We combine the HerschelSpace Observatory PACS (Photoconductor Array Camera and Spectrometer) and SPIRE (Spectral and Photometric Imaging Receiver) photometry with archival WISE (Wide-field Infrared Survey Explorer) photometry to construct the spectral energy distributions (SEDs) for over 300 local (z<0.05), ultrahard X-ray (14-195keV) selected active galactic nuclei (AGN) from the Swift Burst Alert Telescope (BAT) 58-month catalogue. Using a simple analytical model that combines an exponentially cutoff power law with a single temperature modified blackbody, we decompose the SEDs into a host galaxy and AGN component. We calculate dust masses, dust temperatures, and star formation rates (SFRs) for our entire sample and compare them to a stellar mass-matched sample of local non-AGN galaxies. We find AGN host galaxies have systematically higher dust masses, dust temperatures, and SFRs due to the higher prevalence of late-type galaxies to host an AGN, in agreement with previous studies of the Swift/BAT AGN. We provide a scaling to convert X-ray luminosities into 8-1000{mu}m AGN luminosities, as well as determine the best mid-to-far IR colours for identifying AGN-dominated galaxies in the IR regime. We find that for nearly 30 per cent of our sample, the 70{mu}m emission contains a significant contribution from the AGN (>0.5), especially at higher luminosities (L_14-195keV_>10^42.5^erg/s). Finally, we measure the local SFR-AGN luminosity relationship, finding a slope of 0.18, large scatter (0.37 dex), and no evidence for an upturn at high AGN luminosity. We conclude with a discussion on the implications of our results within the context of galaxy evolution with and without AGN
35. AGN-host connection in partially obscured AGNs. I.
ID:
ivo://CDS.VizieR/J/ApJ/679/86
Title:
AGN-host connection in partially obscured AGNs. I.
Short Name:
J/ApJ/679/86
Date:
21 Oct 2021
Publisher:
CDS
Description:
The goal of our serial papers is to examine the evolutionary connection between an active galactic nucleus (AGN) and star formation in the AGN's host galaxy for partially obscured AGNs (i.e., Seyfert 1.8 and 1.9 galaxies). Taking advantage of these galaxies, the properties of both components can be studied together by direct measurements. In this paper, we focus on broad-line composite galaxies (composite AGNs), which are located between the theoretical and empirical separation lines in the [NII]/H{alpha} versus [OIII]/H{beta} diagram. These galaxies are selected from the composite galaxies provided by the SDSS DR4 MPA/JHU catalogs. After we reanalyze the spectra, we perform a fine classification for the 85 composite AGNs in terms of Baldwin-Phillips-Terlevich (BPT) diagrams. All objects located below the three theoretical separation lines are associated with a young stellar population (<1Gyr), while either a young or old stellar population is identified in the individual multiply classified objects. The multiply classified objects with very old stellar populations are located in the LINER region in the [OI]/H{alpha} versus [OIII]/H{beta} diagram. We then consider the connection between AGNs and star formation to derive the key results. The Eddington ratio inferred from the broad H{alpha} emission, the age of the stellar population of the AGN's host as assessed by D_n_(4000), and the line ratio [OI]/H{alpha} are found to be related to each other.
36. AGN-Host Galaxy Connection
ID:
ivo://CDS.VizieR/J/A+A/541/A118
Title:
AGN-Host Galaxy Connection
Short Name:
J/A+A/541/A118
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the results of morphological and colour analysis of X-ray detected AGN in the SXDS field. X-ray data were gathered from the XMM-Newton scientific archive, and were reduced by our team using the standard SAS procedures. The obtained catalogue of 1121 X-ray emitters was cross-matched with the publicly available optical catalogue (Furusawa et al., 2008, Cat. J/ApJS/176/1), using a cross-matched radius of 3 arcsec and obtaining 806 optical counterparts. For these objects the photometric redshifts, K-corrections, morphological, X-ray, and rest-frame colour properties were measured and analysed.
37. AGN host galaxy morphologies in COSMOS
ID:
ivo://CDS.VizieR/J/ApJ/691/705
Title:
AGN host galaxy morphologies in COSMOS
Short Name:
J/ApJ/691/705
Date:
21 Oct 2021
Publisher:
CDS
Description:
We use Hubble Space Telescope/Advanced Camera for Surveys images and a photometric catalog of the Cosmic Evolution Survey (COSMOS) field to analyze morphologies of the host galaxies of ~400 active galactic nucleus (AGN) candidates at redshifts 0.3<z<1.0. We compare the AGN hosts with a sample of nonactive galaxies drawn from the COSMOS field to match the magnitude and redshift distribution of the AGN hosts. We perform two-dimensional surface brightness modeling with GALFIT to yield host galaxy and nuclear point source magnitudes. X-ray-selected AGN host galaxy morphologies span a substantial range that peaks between those of early-type, bulge-dominated and late-type, disk-dominated systems. We also measure the asymmetry and concentration of the host galaxies. Unaccounted for, the nuclear point source can significantly bias results of these measured structural parameters, so we subtract the best-fit point source component to obtain images of the underlying host galaxies. Our concentration measurements reinforce the findings of our two-dimensional morphology fits, placing X-ray AGN hosts between early- and late-type inactive galaxies. AGN host asymmetry distributions are consistent with those of control galaxies.
38. AGN identifications from AKARI and Swift
ID:
ivo://CDS.VizieR/J/ApJ/753/104
Title:
AGN identifications from AKARI and Swift
Short Name:
J/ApJ/753/104
Date:
21 Oct 2021
Publisher:
CDS
Description:
We combine data from two all-sky surveys in order to study the connection between the infrared and hard X-ray (>10keV) properties for local active galactic nuclei (AGNs). The Swift Burst Alert Telescope all-sky survey provides an unbiased, flux-limited selection of hard X-ray-detected AGNs. Cross-correlating the 22 month hard X-ray survey (Tueller et al. 2010, Cat. J/ApJS/186/378) with the AKARI all-sky survey (AKARI/PSCs; Ishihara et al. 2010, Cat. II/297; Yamamura et al. 2010, Cat. II/298), we studied 158 AGNs detected by the AKARI instruments. We find a strong correlation for most AGNs between the infrared (9, 18, and 90{mu}m) and hard X-ray (14-195keV) luminosities, and quantify the correlation for various subsamples of AGNs. Partial correlation analysis confirms the intrinsic correlation after removing the redshift contribution. The correlation for radio galaxies has a slope and normalization identical to that for Seyfert 1 galaxies, implying similar hard X-ray/infrared emission processes in both. In contrast, Compton-thick (CT) sources show a large deficit in the hard X-ray band, because high gas column densities diminish even their hard X-ray luminosities. We propose two photometric diagnostics for source classification: one is an X-ray luminosity versus infrared color diagram, in which type 1 radio-loud AGNs are well isolated from the others in the sample. The other uses the X-ray versus infrared color as a useful redshift-independent indicator for identifying CT AGNs. Importantly, CT AGNs and starburst galaxies in composite systems can also be differentiated in this plane based upon their hard X-ray fluxes and dust temperatures. This diagram may be useful as a new indicator to classify objects in new and upcoming surveys such as WISE and NuSTAR.
39. AGN in IFRS. VLBA observations
ID:
ivo://CDS.VizieR/J/A+A/578/A67
Title:
AGN in IFRS. VLBA observations
Short Name:
J/A+A/578/A67
Date:
21 Oct 2021
Publisher:
CDS
Description:
Infrared-faint radio sources (IFRS) form a new class of galaxies characterised by radio flux densities between tenths and tens of mJy and faint or absent infrared counterparts. It has been suggested that these objects are radio-loud active galactic nuclei (AGNs) at significant redshifts (z>2). Whereas the high redshifts of IFRS have been recently confirmed based on spectroscopic data, the evidence for the presence of AGNs in IFRS is mainly indirect. So far, only two AGNs have been unquestionably confirmed in IFRS based on very long baseline interferometry (VLBI) observations. In this work, we test the hypothesis that IFRS contain AGNs in a large sample of sources using VLBI. We observed 57 IFRS with the Very Long Baseline Array (VLBA) down to a detection sensitivity in the sub-mJy regime and detected compact cores in 35 sources. Our VLBA detections increase the number of VLBI-detected IFRS from 2 to 37 and provide strong evidence that most - if not all - IFRS contain AGNs. We find that IFRS have a marginally higher VLBI detection fraction than randomly selected sources with mJy flux densities at arcsec-scales. Moreover, our data provide a positive correlation between compactness - defined as the ratio of milliarcsec- to arcsec-scale flux density - and redshift for IFRS, but suggest a decreasing mean compactness with increasing arcsec-scale radio flux density. Based on these findings, we suggest that IFRS tend to contain young AGNs whose jets have not formed yet or have not expanded, equivalent to very compact objects. We found two IFRS that are resolved into two components. The two components are spatially separated by a few hundred milliarcseconds in both cases. They might be components of one AGN, a binary black hole, or the result of gravitational lensing.
40. AGN in nearby galaxies
ID:
ivo://CDS.VizieR/J/MNRAS/398/1165
Title:
AGN in nearby galaxies
Short Name:
J/MNRAS/398/1165
Date:
21 Oct 2021
Publisher:
CDS
Description:
Using Spitzer-infrared spectrograph (IRS) spectroscopy, we investigate the ubiquity of active galactic nuclei (AGN) in a complete (~94%), volume-limited sample of the most bolometrically luminous galaxies [L_IR,8-1000um_>=(0.3-20)x10^10^L_{sun}_] to D<15Mpc. Our analyses are based on the detection of the high-excitation emission line [NeV]({lambda}14.32{mu}m) (97.1eV) to unambiguously identify AGN activity. We find that 17 of the 64 infrared (IR) bright galaxies in our sample host AGN activity (~27^+8^_6_%), >=50t of which are not identified as AGN using optical spectroscopy.