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- ID:
- ivo://CDS.VizieR/J/ApJ/701/587
- Title:
- A deep HST H-band imaging survey. II. QUEST QSOs
- Short Name:
- J/ApJ/701/587
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the results from a deep Hubble Space Telescope (HST) NICMOS H-band imaging survey of 28 z<0.3 QSOs from the Palomar-Green (PG) sample. This program is part of QUEST (Quasar/ULIRG Evolution Study) and complements a similar set of data on 26 highly nucleated ULIRGs presented in Paper I (Veilleux et al. 2006ApJ...643..707V). Our analysis indicates that the fraction of QSOs with elliptical hosts is higher among QSOs with undetected far-infrared (FIR) emission, small infrared excess (L_IR_/L_B_<10), and luminous hosts. The hosts of FIR-faint QSOs show a tendency to have less pronounced merger-induced morphological anomalies and larger QSO-to-host luminosity ratios on average than the hosts of FIR-bright QSOs, consistent with late-merger evolution from FIR-bright to FIR-faint QSOs.
- ID:
- ivo://CDS.VizieR/J/ApJ/693/1840
- Title:
- A3266 galaxies at 24um
- Short Name:
- J/ApJ/693/1840
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present Multiband Imaging Photometer observations of the cluster A3266. About 100 spectroscopic cluster members have been detected at 24um. The infrared (IR) luminosity function (LF) in A3266 is very similar to that in the Coma cluster down to the detection limit LIR~10^43^erg/s, suggesting a universal form of the bright-end IR LF for local rich clusters with M~10^15^M_{sun}_. The shape of the bright end of the A3266-Coma composite IR LF is not significantly different from that of nearby field galaxies, but the fraction of IR-bright galaxies (star formation rate (SFR)>0.2M_{sun}_/yr) in both clusters increases with cluster-centric radius. The decrease of the blue galaxy fraction toward the high-density cores only accounts for part of the trend; the fraction of red galaxies with moderate SFRs (0.2M_{sun}_/yr<SFR<1M_{sun}/yr) also decreases with increasing galaxy density. These results suggest that for the IR-bright galaxies nearby rich clusters are distinguished from the field by a lower star forming galaxy fraction, but not by a change in L*_IR_.
- 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/407/2399
- Title:
- AGN activity and black hole mass
- Short Name:
- J/MNRAS/407/2399
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We investigate the role of host galaxy classification and black hole mass (MBH) in a heterogeneous sample of 276 mostly nearby (z<0.1) X-ray and IR-selected active galactic nuclei (AGN).
- 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.
- ID:
- ivo://CDS.VizieR/J/AJ/137/179
- Title:
- AGNs in the Extended Groth Strip Survey
- Short Name:
- J/AJ/137/179
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have employed a reliable technique of classification of active galactic nuclei (AGNs) based on the fit of well sampled spectral energy distributions (SEDs) with a complete set of AGN and starburst galaxy templates. We have compiled UV, optical, and IR data for a sample of 116 AGNs originally selected for their X-ray and mid-IR emissions (96 with single detections and 20 with double optical counterparts). This is the most complete compilation of multiwavelength data for such a large sample of AGN in the Extended Groth Strip. Through these SEDs, we are able to obtain highly reliable photometric redshifts and to distinguish between pure and host-dominated AGNs.
- ID:
- ivo://CDS.VizieR/J/A+A/357/839
- Title:
- AGN 2.5-11um spectroscopy
- Short Name:
- J/A+A/357/839
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present observations over the 2.5-11{mu}m range, with the ISOPHOT-S spectrometer and the ISOCAM imaging camera, of a sample of 57 AGNs and one non-active SB galaxy. The sample is about equally divided into type I (<=1.5; 28 sources) and type II (>1.5; 29 sources) objects.
- ID:
- ivo://CDS.VizieR/J/A+A/602/A123
- Title:
- AGN vs. host galaxy properties in COSMOS field
- Short Name:
- J/A+A/602/A123
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The coeval AGN and galaxy evolution and the observed local relations between SMBHs and galaxy properties suggest some connection or feedback between SMBH growth and galaxy build-up. We looked for correlations between properties of X-ray detected AGN and their FIR detected host galaxies, to find quantitative evidences for this connection, highly debated in the latest years. We exploit the rich multi-wavelength data set available in the COSMOS field for a large sample (692 sources) of AGN and their hosts, in the redshift range 0.1<z<4. We use X-ray data to select AGN and determine their properties (intrinsic luminosity and nuclear obscuration), and broad-band SED fitting to derive host galaxy properties (stellar mass M* and star formation rate SFR). We find that the AGN 2-10keV luminosity (LX) and the host 8-1000um star formation luminosity (LSFIR) are significantly correlated. However, the average host LSFIR has a flat distribution in bins of AGN LX, while the average AGN LX increases in bins of host LSFIR, with logarithmic slope of ~0.7, in the redshifts range 0.4<z<1.2. We also discuss the comparison between the distribution of these two quantities and the predictions from hydro-dynamical simulations. Finally we find that the average column density (NH) shows a positive correlation with the host M*, at all redshifts, but not with the SFR (or LSFIR). This translates into a negative correlation with specific SFR. Our results are in agreement with the idea that BH accretion and SF rates are correlated, but occur with different variability time scales. The presence of a positive correlation between NH and host M* suggests that the X-ray NH is not entirely due to the circum-nuclear obscuring torus, but may also include a contribution from the host galaxy.
- ID:
- ivo://CDS.VizieR/J/A+A/605/A74
- Title:
- AKARI fluxes of ATLAS3D early-type galaxies
- Short Name:
- J/A+A/605/A74
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The star formation properties of early-type galaxies (ETGs) are currently the subject of considerable interest, particularly whether they differ from the star formation properties of gas-rich spirals. We perform a systematic study of star formation in a large sample of local ETGs with polycyclic aromatic hydrocarbon (PAH) and dust emission, focusing on the star formation rates (SFRs) and star formation efficiencies (SFEs) of the galaxies. Our sample is composed of the 260 ETGs from the ATLAS^3D^ survey, from which we used the cold gas measurements (HI and CO). We estimated the SFRs from stellar, PAH, and dust fits to spectral energy distributions created from new AKARI measurements and with literature data from WISE and 2MASS. The mid-infrared luminosities of non-CO-detected galaxies are well correlated with their stellar luminosities, showing that they trace (circum)stellar dust emission. CO-detected galaxies show an excess above these correlations, uncorrelated with their stellar luminosities, indicating that they likely contain PAHs and dust of interstellar origin. PAH and dust luminosities of CO-detected galaxies show tight correlations with their molecular gas masses; the derived current SFRs are typically 0.01-1M_{sun}_/yr. These SFRs systematically decrease with stellar age at fixed stellar mass, while they correlate nearly linearly with stellar mass at fixed age. The majority of local ETGs follow the same star formation law as local star-forming galaxies and their current SFEs do not depend on either stellar mass or age. Our results clearly indicate that molecular gas is fueling current star formation in local ETGs, which appear to acquire this gas via mechanisms regulated primarily by stellar mass. The current SFEs of local ETGs are similar to those of local star-forming galaxies, indicating that their low SFRs are likely due to smaller cold gas fractions rather than a suppression of star formation.
