- 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_.
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Search Results
- ID:
- ivo://CDS.VizieR/J/ApJS/234/33
- Title:
- A GBT survey of large Galactic HII regions
- Short Name:
- J/ApJS/234/33
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- As part of our ongoing HII Region Discovery Survey (HRDS), we report the Green Bank Telescope detection of 148 new angularly large Galactic HII regions in radio recombination line (RRL) emission. Our targets are located at a declination of {delta}>-45{deg}, which corresponds to 266{deg}>l>-20{deg} at b=0{deg}. All sources were selected from the Wide-field Infrared Survey Explorer Catalog of Galactic HII Regions, and have infrared angular diameters >=260". The Galactic distribution of these "large" HII regions is similar to that of the previously known sample of Galactic HII regions. The large HII region RRL line width and peak line intensity distributions are skewed toward lower values, compared with that of previous HRDS surveys. We discover seven sources with extremely narrow RRLs <10km/s. If half the line width is due to turbulence, these seven sources have thermal plasma temperatures <1100K. These temperatures are lower than any measured for Galactic HII regions, and the narrow-line components may arise instead from partially ionized zones in the HII region photodissociation regions. We discover G039.515+00.511, one of the most luminous HII regions in the Galaxy. We also detect the RRL emission from three HII regions with diameters >100pc, making them some of the physically largest known HII regions in the Galaxy. This survey completes the HRDS HII region census in the Northern sky, where we have discovered 887 HII regions and more than doubled the size of the previously known census of Galactic HII regions.
- 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/ApJS/248/3
- Title:
- A 4-6GHz RRL survey in the Milky Way
- Short Name:
- J/ApJS/248/3
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We performed a radio recombination line (RRL) survey to construct a high-mass star-forming region (HMSFR) sample in the Milky Way based on the all-sky Wide-Field Infrared Survey Explorer point-source catalog. The survey was observed with the Shanghai 65m Tianma radio telescope covering 10 hydrogen RRL transitions ranging from H98{alpha} to H113{alpha} (corresponding to the rest frequencies of 4.5-6.9GHz) simultaneously. Out of 3348 selected targets, we identified an HMSFR sample consisting of 517 sources traced by RRLs; a large fraction of this sample (486) is located near the Galactic Plane (|b|<2{deg}). In addition to the hydrogen RRLs, we also detected helium and carbon RRLs toward 49 and 23 sources, respectively. We crossmatch the RRL detections with the 6.7 methanol maser sources built up in previous works for the same target sample. As a result, 103 HMSFR sources were found to harbor both emissions. In this paper, we present the HMSFR catalog accompanied by the measured RRL line properties and a correlation with our methanol maser sample, which is believed to trace massive stars at earlier stages. The construction of an HMSFR sample consisting of sources in various evolutionary stages indicated by different tracers is fundamental for future studies of high-mass star formation in such regions.
- ID:
- ivo://CDS.VizieR/J/ApJS/91/347
- Title:
- A 5-GHz VLA Survey of the Galactic Plane
- Short Name:
- J/ApJS/91/347
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have used the VLA to survey the inner Galaxy (|b|<0.4{deg}, l=350-40{deg}) at 5GHz to a limiting sensitivity of between 2.5 and 10mJy. The survey has resulted in a catalog of 1272 discrete sources (including 100 sources outside the formal survey area) of which we have tentatively identified ~450 as ultracompact H II regions and ~45 as planetary nebulae. Approximately 30% of the radio sources are detected in the IRAS Point Source Catalog. The results confirm a scale height of only 30pc for ultracompact H II regions. We show that source lists generated from the IRAS Point Source Catalog alone suffer serious effects; the combination of the IRAS and radio surveys allows us to produce a much more complete census of the regions of massive star formation in our Galaxy.
- 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/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/MNRAS/486/4290
- Title:
- AGN-driven winds through IR emission. II.
- Short Name:
- J/MNRAS/486/4290
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The global influence of AGN-driven outflows remains uncertain, due to a lack of large samples with accurately-determined outflow properties. In the second paper of this series, we determine the mass and energetics of ionized outflows is 234 type II AGN, the largest such sample to date, by combining the infrared emission of the dust in the wind (Paper I, Baron & Netzer, 2019MNRAS.482.3915B) with the emission line properties. We provide new general expressions for the properties of the outflowing gas, which depend on the ionization state of the gas. We also present a novel method to estimate the electron density in the outflow, based on optical line ratios and on the known location of the wind. The inferred electron densities, n_e_~10^4.5^cm^^-3^, are two orders of magnitude larger than typically assumed in most other cases of ionized outflows. We argue that the discrepancy is due to the fact that the commonly-used [SII]-based method underestimates the true density by a large factor. As a result, the inferred mass outflow rates and kinetic coupling efficiencies are dM/dt_out_~10^-2^(dM_{sun}_/yr) and epsilon=dE/dt_kin_/L_bol_~10^-5^ respectively, 1-2 orders of magnitude lower than previous estimates. Our analysis suggests the existence of a significant amount of neutral atomic gas at the back of the outflowing ionized gas clouds, with mass that is a factor of a few larger than the observed ionized gas mass. This has significant implications for the estimated mass and energetics of such flows.
- 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/other/APh/26.282
- Title:
- AGN neutrino source candidates
- Short Name:
- J/other/APh/26.2
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The sensitivity of a search for sources of TeV neutrinos can be improved by grouping potential sources together into generic classes in a procedure that is known as source stacking. In this paper, we define catalogs of Active Galactic Nuclei (AGN) and use them to perform a source stacking analysis. The grouping of AGN into classes is done in two steps: first, AGN classes are defined, then, sources to be stacked are selected assuming that a potential neutrino flux is linearly correlated with the photon luminosity in a certain energy band (radio, IR, optical, keV, GeV, TeV). Lacking any secure detailed knowledge on neutrino production in AGN, this correlation is motivated by hadronic AGN models, as briefly reviewed in this paper. The source stacking search for neutrinos from generic AGN classes is illustrated using the data collected by the AMANDA-II high-energy neutrino detector during the year 2000. No significant excess for any of the suggested groups was found.
