- ID:
- ivo://CDS.VizieR/J/A+A/407/899
- Title:
- Core dominance in extragalactic radio sources
- Short Name:
- J/A+A/407/899
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this paper, based on a paper by Liu and Zhang (2002, Cat. <J/A+A/381/757>), we have chosen a sample of 542 extragalactic sources (27 BL Lac objects, 300 galaxies (radio galaxies and Seyfert galaxies), and 215 quasars), for which we have calculated the core-dominance parameters and investigated the relation between core-dominance parameter and the core and extended luminosities. The core-dominance parameter of galaxies is smaller than that in quasars, which is smaller than that in BL Lac objects.
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Search Results
- ID:
- ivo://CDS.VizieR/J/ApJ/696/1195
- Title:
- COSMOS AGN spectroscopic survey. I.
- Short Name:
- J/ApJ/696/1195
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present optical spectroscopy for an X-ray and optical flux-limited sample of 677 XMM-Newton selected targets covering the 2deg^2^ Cosmic Evolution Survey field, with a yield of 485 high-confidence redshifts. The majority of the spectra were obtained over three seasons (2005-2007) with the Inamori Magellan Areal Camera and Spectrograph instrument on the Magellan (Baade) telescope. We also include in the sample previously published Sloan Digital Sky Survey spectra and supplemental observations with MMT/Hectospec. We detail the observations and classification analyses. The survey is 90% complete to flux limits of f_0.5-10keV_>8x10^-16-^erg/cm^2^/s and i^+^_AB_<22, where over 90% of targets have high-confidence redshifts. Making simple corrections for incompleteness due to redshift and spectral type allows for a description of the complete population to i^+^_AB_<23. The corrected sample includes a 57% broad emission line (Type 1, unobscured) active galactic nucleus (AGN) at 0.13<z<4.26, 25% narrow emission line (Type 2, obscured) AGN at 0.07<z<1.29, and 18% absorption line (host-dominated, obscured) AGN at 0<z<1.22 (excluding the stars that made up 4% of the X-ray targets). We show that the survey's limits in X-ray and optical fluxes include nearly all X-ray AGNs (defined by L_0.5-10keV_>3x10^42^erg/s) to z<1, of both optically obscured and unobscured types.
- ID:
- ivo://CDS.VizieR/J/AJ/143/145
- Title:
- Emission-line objects from ALFALFA H{alpha} survey
- Short Name:
- J/AJ/143/145
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- During a wide-field narrowband H{alpha} imaging survey, we noted the presence of numerous isolated emission-line point sources in the data. These objects could represent ultra-low-luminosity galaxies at low-redshift (detection via H{alpha}), isolated extragalactic HII regions associated with the galaxy targeted by the original observation, or background galaxies or QSOs where strong emission lines (most often [OIII]{lambda}5007) redshift into our narrowband filter. We have carried out a systematic search for these "H{alpha} dots" in over 200 15x15arcmin fields. To date we have cataloged 61 candidate emission-line sources in roughly 11.7deg^2^. The sample has a median R magnitude of 19.5, and detects objects as faint as R=22.6. Follow-up spectroscopy reveals that ~85% of the candidates are bona fide emission-line objects, with roughly 60% of the real sources being lower-redshift objects (detection via H{alpha}) and 40% being higher-redshift objects detected via [OIII] emission or some other emission line. Here we present the results of our initial survey and follow-up spectroscopy. We use our sample to study the properties (including star-formation rates and metal abundances) of low-luminosity star-forming galaxies in the nearby universe and of low-metallicity star-forming galaxies at z~0.33.
- ID:
- ivo://CDS.VizieR/J/MNRAS/366/480
- Title:
- Emission-line properties of Seyfert 2 nuclei
- Short Name:
- J/MNRAS/366/480
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This is the third paper of a series devoted to the study of the global properties of Joguet's sample (2001A&A...380...19J) of 79 nearby galaxies observable from the southern hemisphere, of which 65 are Seyfert 2 galaxies. We use the population synthesis models of Paper II (Cid Fernandes et al., 2004MNRAS.355..273C) to derive 'pure' emission-line spectra for the Seyfert 2 galaxies in the sample, and thus explore the statistical properties of the nuclear nebular components and their relation to the stellar populations.
- ID:
- ivo://CDS.VizieR/J/A+A/614/A94
- Title:
- ESO 362-G18 datacube
- Short Name:
- J/A+A/614/A94
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present two-dimensional stellar and gaseous kinematics of the inner 0.7x1.2kpc^2^ of the Seyfert 1.5 galaxy ESO 362-G18, derived from optical (4092-7338{AA}) spectra obtained with the GMOS integral field spectrograph on the Gemini South telescope at a spatial resolution of 170 pc and spectral resolution of 36km/s. ESO 362-G18 is a strongly perturbed galaxy of morphological type Sa or S0/a, with a minor merger approaching along the NE direction. Previous studies have shown that the [OIII] emission shows a fan-shaped extension of ~10" to the SE. We detect the [OIII] doublet, [NII] and H{alpha} emission lines throughout our FOV. The stellar kinematics is dominated by circular motions in the galaxy plane, with a kinematic position angle of ~137{deg} and is centred approximately on the continuum peak. The gas kinematics is also dominated by rotation, with kinematic position angles ranging from 122{deg} to 139{deg}, projected velocity amplitudes of the order of 100km/s, and a mean velocity dispersion of 100km/s. A double-Gaussian fit to the [OIII]{lambda}5007 and H{alpha} lines, which have the highest signal to noise ratios of the emission lines, reveal two kinematic components: (1) a component at lower radial velocities which we interpret as gas rotating in the galactic disk; and (2) a component with line of sight (LOS) velocities 100-250km/s higher than the systemic velocity, interpreted as originating in the outflowing gas within the AGN ionization cone. We estimate a mass outflow rate of 7.4x10^-2^M_{sun}_/yr in the SE ionization cone (this rate doubles if we assume a biconical configuration), and a mass accretion rate on the supermassive black hole (SMBH) of 2.2x10^-2^M_{sun}_/yr. The total ionized gas mass within 84pc of the nucleus is 3.3x10^5^M_{sun}_; infall velocities of ~34km/s in this gas would be required to feed both the outflow and SMBH accretion.
- ID:
- ivo://CDS.VizieR/J/ApJ/884/11
- Title:
- Exploring 6 AGN dusty torus models. II.
- Short Name:
- J/ApJ/884/11
- Date:
- 04 Dec 2021
- Publisher:
- CDS
- Description:
- This is the second in a series of papers devoted to exploring a set of six dusty models of active galactic nuclei (AGN) with available spectral energy distributions. These models are the smooth torus by Fritz+ (2006MNRAS.366..767F), the clumpy torus by Nenkova+ (2008ApJ...685..147N and 2008ApJ...685..160N), the clumpy torus by Honig & Kishimoto (2010A&A...523A..27H), the two-phase torus by Siebenmorgen+ (2015A&A...583A.120S), the two-phase torus by Stalevski+ (2012MNRAS.420.2756S and 2016MNRAS.458.2288S), and the wind model by Honig & Kishimoto (2017ApJ...838L..20H). The first paper explores discrimination among models and the parameter restriction using synthetic spectra. Here we perform spectral fitting of a sample of 110 AGN drawn from the Swift/BAT survey with Spitzer/IRS spectroscopic data. The aim is to explore which is the model that describes better the data and the resulting parameters. The clumpy wind-disk model by Honig & Kishimoto provides good fits for ~50% of the sample, and the clumpy torus model by Nenkova+ is good at describing ~30% of the objects. The wind-disk model by Honig & Kishimoto is better for reproducing the mid-infrared spectra of type 1 Seyferts (with 60% of the type 1 Seyferts well reproduced by this model compared to the 10% well represented by the clumpy torus model by Nenkova+), while type 2 Seyferts are equally fitted by both models (roughly 40% of the type 2 Seyferts). Large residuals are found irrespective of the model used, indicating that the AGN dust continuum emission is more complex than predicted by the models or that the parameter space is not well sampled. We found that all the resulting parameters for our AGN sample are roughly constrained to 10%-20% of the parameter space. Contrary to what is generally assumed, the derived outer radius of the torus is smaller (reaching up to a factor of ~5 smaller for 10pc tori) for the smooth torus by Fritz+ and the two-phase torus by Stalevski+ than the one derived from the clumpy torus by Nenkova+ Covering factors and line-of-sight viewing angles strongly depend on the model used. The total dust mass is the most robust derived quantity, giving equivalent results for four of these models.
- ID:
- ivo://CDS.VizieR/J/A+A/549/A51
- Title:
- Extended CO structures in NGC6240
- Short Name:
- J/A+A/549/A51
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present deep CO(1-0) observations of NGC6240 performed with the IRAM Plateau de Bure Interferometer (PdBI). NGC6240 is the prototypical example of a major galaxy merger in progress, caught at an early stage, with an extended, strongly-disturbed butterfly- like morphology and a heavily obscured active nucleus in the core of each progenitor galaxy.
- ID:
- ivo://CDS.VizieR/J/other/PBeiO/18.7
- Title:
- Far infrared Seyfert galaxies
- Short Name:
- J/other/PBeiO/18
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Confusing sources of Seyfert and HII galaxies in IRAS point source catalogue may be caused by companion objects of those galaxies. Comparison between confused galaxies and non-confused galaxies have been made. The preliminary comparison shows that confused galaxies are fainter than nonconfused galaxies generally, and colour diagrams illustrate that confused Seyferts are separated from nonconfused Seyferts obviously.
- ID:
- ivo://CDS.VizieR/J/MNRAS/426/2522
- Title:
- FeK lines in Seyfert 1 galaxies
- Short Name:
- J/MNRAS/426/2522
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We construct full broad-band models in an analysis of Suzaku observations of nearby Seyfert 1 active galactic nuclei (AGN) (z<=0.2) with exposures >50ks and with greater than 30000 counts in order to study their iron line profiles. This results in a sample of 46 objects and 84 observations. After a full modelling of the broad-band Suzaku and Swift-Burst Alert Telescope data (0.6-100keV), we find complex warm absorption is present in 59 per cent of the objects in this sample which has a significant bearing upon the derived FeK region parameters. Meanwhile 35 per cent of the 46 objects require some degree of high column density partial coverer in order to fully model the hard X-ray spectrum. We also find that a large number of the objects in the sample (22 per cent) require high velocity, high ionization outflows in the FeK region resulting from FeXXV and FeXXVI. A further four AGN feature highly ionized FeK absorbers consistent with zero outflow velocity, making a total of 14/46 (30%) AGN in this sample showing evidence for statistically significant absorption in the FeK region.
- ID:
- ivo://CDS.VizieR/J/AJ/127/1959
- Title:
- 1.4GHz emission of KISS emission-line galaxies
- Short Name:
- J/AJ/127/1959
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have searched the Faint Images of the Radio Sky at Twenty centimeters (FIRST, <VIII/71>) and the NRAO VLA Sky Survey (NVSS, <VIII/65>) 1.4GHz radio surveys for sources that are coincident with emission-line galaxy (ELG) candidates from the KPNO International Spectroscopic Survey (KISS). A total of 207 of the 2157 KISS ELGs (~10%) in the first two H{alpha}-selected survey lists (Cats <J/AJ/121/66>, <J/AJ/127/1943>) were found to possess radio detections in FIRST, NVSS, or both. Follow-up spectra exist for all of the radio detections, allowing us to determine the activity type (star-forming vs. active nucleus) for the entire sample. We explore the properties of the radio-detected KISS galaxies in order to gain a better insight into the nature of radio-emitting galaxies in the local universe (z<0.1). Because of the selection technique used for KISS, our radio ELGs represent a quasivolume-limited sample, which allows us to develop a clearer picture of the radio galaxy population at low redshift. Nearly two-thirds of the KISS radio galaxies are starburst or star-forming galaxies, which is in stark contrast to the results of flux-limited radio surveys, which are dominated by active galactic nuclei (AGNs) and elliptical galaxies (i.e., classical radio galaxies).
