- 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.
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Search Results
- 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/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.
- 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.
- ID:
- ivo://CDS.VizieR/J/ApJ/640/167
- Title:
- AGNs and ULIRGs in the CDF-South
- Short Name:
- J/ApJ/640/167
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We investigate the nature of a sample of 92 Spitzer MIPS 24{mu}m- selected galaxies in the CDF-S, showing power-law-like emission in the Spitzer IRAC 3.6-8{mu}m bands. The main goal is to determine whether the galaxies not detected in X-rays (47% of the sample) are part of the hypothetical population of obscured AGNs not detected even in deep X-ray surveys.
- ID:
- ivo://CDS.VizieR/J/A+A/594/A54
- Title:
- A 1689 HAWK-I J-band image
- Short Name:
- J/A+A/594/A54
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a ground-based, near-infrared search for lensed supernovae behind the massive cluster Abell 1689 at z=0.18, which is one of the most powerful gravitational telescopes that nature provides. Our survey was based on multi-epoch J-band observations with the HAWK-I instrument on VLT, with supporting optical data from the Nordic Optical Telescope. Our search resulted in the discovery of five photometrically classified, core-collapse supernovae with high redshifts of 0.671<z<1.703 and magnifications in the range {DELTA}m=-0.31 to -1.58mag, as calculated from lensing models in the literature. Owing to the power of the lensing cluster, the survey had the sensitivity to detect supernovae up to very high redshifts, z~3, albeit for a limited region of space. We present a study of the core-collapse supernova rates for 0.4<=z<2.9, and find good agreement with previous estimates and predictions from star formation history. During our survey, we also discovered two Type Ia supernovae in A 1689 cluster members, which allowed us to determine the cluster Ia rate to be 0.14+0.19-0.09+/-0.01SNuB*h^2^ (SNuB=10^-12^SNeL_{sun},B_^-1^yr^-1^), where the error bars indicate 1{sigma} confidence intervals, statistical and systematic, respectively. The cluster rate normalized by the stellar mass is 0.10+0.13-0.096+/-0.02 in SNuM*h^2^ (SNuM=10^-12^SNeM_{sun}_^-1^yr^-1^). Furthermore, we explore the optimal future survey for improving the core-collapse supernova rate measurements at z>~2 using gravitational telescopes, and for detections with multiply lensed images, and we find that the planned WFIRST space mission has excellent prospects.
- ID:
- ivo://CDS.VizieR/II/298
- Title:
- AKARI/FIS All-Sky Survey Point Source Catalogues
- Short Name:
- II/298
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The AKARI Infrared Astronomical Satellite observed the whole sky in the far infrared (50-180{mu}m) and the mid-infrared (9 and 18{mu}m) between May 2006 and August 2007 (Murakami et al. 2007PASJ...59S.369M) The AKARI/FIS All-Sky Survey Bright Source Catalog Version 1.0 provides positions and fluxes for 427071 point sources in the 4 far-infrared wavelengths centered at 65, 90, 140 and 160{mu}m (see filter characteristics in the "Note (1)" section below)
- ID:
- ivo://CDS.VizieR/J/A+A/514/A2
- Title:
- AKARI/HIP and AKARI/2MASS samples
- Short Name:
- J/A+A/514/A2
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The AKARI, a Japanese infrared space mission, has performed an All-Sky Survey in six infrared-bands from 9 to 180um with higher spatial resolutions and better sensitivities than the Infrared Astronomical Satellite (IRAS). We investigate the mid-infrared (9 and 18um) point source catalog (PSC) obtained with the Infrared Camera (IRC) onboard AKARI, in order to understand the infrared nature of the known objects and to identify previously unknown objects. Color-color diagrams and a color-magnitude diagram were plotted with the AKARI-IRC PSC and other available all-sky survey catalogs. We combined the Hipparcos astrometric catalog and the 2MASS all-sky survey catalog with the AKARI-IRC PSC. We furthermore searched literature and SIMBAD astronomical database for object types, spectral types, and luminosity classes. We identified the locations of representative stars and objects on the color-magnitude and color-color diagram schemes. The properties of unclassified sources can be inferred from their locations on these diagrams.
- ID:
- ivo://CDS.VizieR/II/297
- Title:
- AKARI/IRC mid-IR all-sky Survey
- Short Name:
- II/297
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The AKARI Infrared Astronomical Satellite observed the whole sky in the far infrared (50-180{mu}m) and the mid-infrared (9 and 18{mu}m) between May 2006 and August 2007 (Murakami et al. 2007PASJ...59S.369M) The AKARI/IRC Point Source Catalogue Version 1.0 provides positions and fluxes for 870,973 sources observed with the InfraRed Camera (IRC): 844,649 sources in the S9W filter, and 194,551 sources in the L18W filter; the "Note (1)" section below provides a summary of the IRC filter characteristics.
- ID:
- ivo://CDS.VizieR/J/AJ/145/32
- Title:
- AKARI-LMC Near-infrared Spectroscopic Catalog
- Short Name:
- J/AJ/145/32
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We performed a near-infrared spectroscopic survey toward an area of ~10deg^2^ of the Large Magellanic Cloud (LMC) with the infrared satellite AKARI. Observations were carried out as part of the AKARI Large-area Survey of the Large Magellanic Cloud (LSLMC). The slitless multi-object spectroscopic capability of the AKARI/IRC enabled us to obtain low-resolution (R~20) spectra in 2-5{mu}m for a large number of point sources in the LMC. As a result of the survey, we extracted about 2000 infrared spectra of point sources. The data are organized as a near-infrared spectroscopic catalog. The catalog includes various infrared objects such as young stellar objects (YSOs), asymptotic giant branch (AGB) stars, supergiants, and so on. It is shown that 97% of the catalog sources have corresponding photometric data in the wavelength range from 1.2 to 11{mu}m, and 67% of the sources also have photometric data up to 24{mu}m. The catalog allows us to investigate near-infrared spectral features of sources by comparison with their infrared spectral energy distributions. In addition, it is estimated that about 10% of the catalog sources are observed at more than two different epochs. This enables us to study a spectroscopic variability of sources by using the present catalog. Initial results of source classifications for the LSLMC samples are presented. We classified 659 LSLMC spectra based on their near-infrared spectral features by visual inspection. As a result, it is shown that the present catalog includes 7 YSOs, 160 C-rich AGBs, 8 C-rich AGB candidates, 85 O-rich AGBs, 122 blue and yellow supergiants, 150 red super giants, and 128 unclassified sources. Distributions of the classified sources on the color-color and color-magnitude diagrams are discussed in the text. Continuous wavelength coverage and high spectroscopic sensitivity in 2-5{mu}m can only be achieved by space observations. This is an unprecedented large-scale spectroscopic survey toward the LMC in the near-infrared. A large number of near-infrared spectral data provided by the survey possess scientific potential that can be applied to various studies. In this paper, we present the details of the spectroscopic survey and the catalog, and discuss its scientific applications.
