Search

Start Over Validation Level 2
671. AGN effect on cold gas in distant SFGs
ID:
ivo://CDS.VizieR/J/A+A/654/A165
Title:
AGN effect on cold gas in distant SFGs
Short Name:
J/A+A/654/A165
Date:
22 Feb 2022
Publisher:
CDS
Description:
In the framework of a systematic study with the ALMA interferometer of infrared (IR)-selected main sequence and starburst galaxies at z~1-1.7 at typical ~1" resolution, we report on the effects of mid-IR and X-ray detected active galactic nuclei (AGN) on the reservoirs and excitation of molecular gas in a sample of 55 objects. We find widespread detectable nuclear activity in ~30% of the sample. The presence of dusty tori influences the IR spectral energy distribution of galaxies, as highlighted by the strong correlation among the AGN contribution to the total IR luminosity budget (fAGN=LIR_AGN_/LIR), its hard X-ray emission, and the Rayleigh-Jeans to mid-IR (S_1.2mm_/S_24um_) observed color with evident consequences on the ensuing empirical star formation rate estimates. Nevertheless, we find only marginal effects of the presence and strength of AGN on the carbon monoxide CO (J=2,4,5,7) or neutral carbon ([CI](3P1-3P0), [CI](3P2-3P1)) line luminosities and on the derived molecular gas excitation as gauged by line ratios and the full spectral line energy distributions. The [CI] and CO emission up to J=5,7 thus primarily traces the properties of the host in typical IR luminous galaxies. However, our analysis highlights the existence of a large variety of line luminosities and ratios despite the homogeneous selection. In particular, we find a sparse group of AGN-dominated sources with the highest LIR_AGN_/LIR_SFR_>=3 ratios that are more luminous in CO(5-4) than what predicted by the L_CO(5-4)_-LIR_SFR_ relation, which might be the result of the nuclear activity. For the general population, our findings translate into AGN having minimal effects on quantities such as gas and dust fractions and star formation efficiencies. If anything, we find hints of a marginal tendency of AGN hosts to be compact at far-IR wavelengths and to display 1.8x larger dust optical depths. In general, this is consistent with a marginal impact of the nuclear activity on the gas reservoirs and star formation in average star-forming AGN hosts with LIR>5x10^11^L_{sun}_, typically under-represented in surveys of quasars and sub-millimeter galaxies.
672. AGN emission line properties
ID:
ivo://CDS.VizieR/J/ApJS/143/257
Title:
AGN emission line properties
Short Name:
J/ApJS/143/257
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present measurements of the UV/optical emission line parameters in a sample of 158 active galactic nuclei observed with the Faint Object Spectrograph on the Hubble Space Telescope (HST), prior to the installation of COSTAR. We use an automated technique that accounts for galactic reddening, includes iron emission blends, galactic and intrinsic absorption lines, and performs multicomponent fits to the emission line profiles. We present measured line parameters (equivalent width and FWHM) for a large number (28) of different UV/optical lines, including upper limits for undetected lines.
673. 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.
674. 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.
675. 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.
676. AGN from RASS and SDSS DR5
ID:
ivo://CDS.VizieR/J/AJ/133/313
Title:
AGN from RASS and SDSS DR5
Short Name:
J/AJ/133/313
Date:
21 Oct 2021
Publisher:
CDS
Description:
We describe further results of a program aimed at yielding ~104 fully characterized optical identifications of ROSAT X-ray sources. Our program employs X-ray data from the ROSAT All Sky Survey (RASS) and both optical imaging and spectroscopic data from the Sloan Digital Sky Survey (SDSS). RASS/SDSS data from 5740deg^2^ of sky spectroscopically covered in SDSS Data Release 5 provide an expanded catalog of 7000 confirmed quasars and other active galactic nuclei (AGNs) that are probable RASS identifications. Again, in our expanded catalog the identifications as X-ray sources are statistically secure, with only a few percent of the SDSS AGNs likely to be randomly superposed on unrelated RASS X-ray sources.
677. 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.
678. 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
679. 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.
680. 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.

Limit your search

more »

more »

more »

more »

more »

more »

more »

more »