- ID:
- ivo://CDS.VizieR/J/MNRAS/431/194
- Title:
- Selecting IRAC counterparts to SMGs
- Short Name:
- J/MNRAS/431/194
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a new submm/mm galaxy counterpart identification technique which builds on the use of Spitzer Infrared Array Camera (IRAC) colours as discriminators between likely counterparts and the general IRAC galaxy population. Using 102 radio- and Submillimeter Array-confirmed counterparts to AzTEC sources across three fields [Great Observatories Origins Deep Survey-North, -South and Cosmic Evolution Survey (COSMOS)], we develop a non-parametric IRAC colour-colour characteristic density distribution, which, when combined with positional uncertainty information via likelihood ratios, allows us to rank all potential IRAC counterparts around submillimetre galaxies (SMGs) and calculate the significance of each ranking via the reliability factor. We report all robust and tentative radio counterparts to SMGs, the first such list available for AzTEC/COSMOS, as well as the highest ranked IRAC counterparts for all AzTEC SMGs in these fields as determined by our technique. We demonstrate that the technique is free of radio bias and thus applicable regardless of radio detections. For observations made with a moderate beam size (~18"), this technique identifies ~85% of SMG counterparts. For much larger beam sizes (>~30"), we report identification rates of 33-49%. Using simulations, we demonstrate that this technique is an improvement over using positional information alone for observations with facilities such as AzTEC on the Large Millimeter Telescope and Submillimeter Common User Bolometer Array 2 on the James Clerk Maxwell Telescope.
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Search Results
- ID:
- ivo://CDS.VizieR/J/MNRAS/453/3729
- Title:
- Sersic + exponential disc morphologies in Coma
- Short Name:
- J/MNRAS/453/3729
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Galaxies are not limited to simple spheroid or bulge + disc morphologies. We explore the diversity of internal galaxy structures in the Coma Cluster across a wide range of luminosities (-17>Mg>-22) and cluster-centric radii (0<r_cluster_<1.3r_200_) through analysis of deep Canada-France-Hawaii Telescope i-band imaging. We present 2D multicomponent decomposition via galfit, encompassing a wide range of candidate model morphologies with up to three photometric components. Particular focus is placed on early-type galaxies with outer discs (i.e. S0s), and deviations from simple ('unbroken') exponential discs. Rigorous filtering ensures that each model component provides a statistically significant improvement to the goodness-of-fit. The majority of Coma Cluster members in our sample (478 of 631) are reliably fitted by symmetric structural models. Of these, 134 (28 percent) are single Sersic objects, 143 (30 percent) are well-described by 2-component structures, while 201 (42 percent) require more complex models. Multicomponent Sersic galaxies resemble compact pseudo-bulges (n~2, R_e_~4kpc) surrounded by extended Gaussian-like outer structures (R_e_>10kpc). 11 percent of galaxies (N=52) feature a break in their outer profiles, indicating 'truncated' or 'antitruncated' discs. Beyond the break radius, truncated galaxies are structurally consistent with exponential discs, disfavouring physical truncation as their formation mechanism. Bulge luminosity in antitruncated galaxies correlates strongly with galaxy luminosity, indicating a bulge-enhancing origin for these systems. Both types of broken disc are found overwhelmingly (>70 percent) in 'barred' galaxies, despite a low measured bar fraction for Coma (20+/-2 percent). Thus, galaxy bars play an important role in formation of broken disc structures. No strong variation in galaxy structure is detected with projected cluster-centric radius.
- ID:
- ivo://CDS.VizieR/J/A+AS/116/157
- Title:
- SEST obs. of extragalactic radiosources
- Short Name:
- J/A+AS/116/157
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Flux densities of 155 extragalactic radio sources observed with the SEST telescope at 3mm and 1.3mm are presented. The observations were performed from October 1987 to June 1994. In addition to the flux density tables we have plotted the flux density curves for some of the most frequently observed sources.
3204. Seven-year WMAP catalog
- ID:
- ivo://CDS.VizieR/J/ApJS/192/15
- Title:
- Seven-year WMAP catalog
- Short Name:
- J/ApJS/192/15
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present updated estimates of Galactic foreground emission using seven years of WMAP data. Using the power spectrum of differences between multi-frequency template-cleaned maps, we find no evidence for foreground contamination outside of the updated (KQ85y7) foreground mask. We place a 15uK upper bound on rms foreground contamination in the cleaned maps used for cosmological analysis. Further, the cleaning process requires only three power-law foregrounds outside of the mask. We find no evidence for polarized foregrounds beyond those from soft (steep-spectrum) synchrotron and thermal dust emission; in particular we find no indication in the polarization data of an extra "haze" of hard synchrotron emission from energetic electrons near the Galactic center. We provide an updated map of the cosmic microwave background (CMB) using the internal linear combination method, updated foreground masks, and updates to point source catalogs using two different techniques. With additional years of data, we now detect 471 point sources using a five-band technique and 417 sources using a three-band CMB-free technique. In total there are 62 newly detected point sources, a 12% increase over the five-year release.
- ID:
- ivo://CDS.VizieR/J/ApJ/705/14
- Title:
- Seyfert galaxies in the mid-IR
- Short Name:
- J/ApJ/705/14
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- An analysis of archival mid-infrared (mid-IR) spectra of Seyfert galaxies from the Spitzer Space Telescope observations is presented. We characterize the nature of the mid-IR active nuclear continuum by subtracting a template starburst spectrum from the Seyfert spectra. The long wavelength part of the spectrum contains a strong contribution from the starburst-heated cool dust; this is used to effectively separate starburst-dominated Seyferts from those dominated by the active nuclear continuum. Within the latter category, the strength of the active nuclear continuum drops rapidly beyond ~20um. On average, type 2 Seyferts have weaker short-wavelength active nuclear continua as compared to type 1 Seyferts. Type 2 Seyferts can be divided into two types, those with strong polycyclic aromatic hydrocarbon (PAH) bands and those without.
- ID:
- ivo://CDS.VizieR/J/ApJ/788/159
- Title:
- 17 Seyfert 1 galaxies light curves
- Short Name:
- J/ApJ/788/159
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of a dust reverberation survey for 17 nearby Seyfert 1 galaxies, which provides the largest homogeneous data collection for the radius of the innermost dust torus. A delayed response of the K-band light curve after the V-band light curve was found for all targets, and 49 measurements of lag times between the flux variation of the dust emission in the K band and that of the optical continuum emission in the V band were obtained by the cross-correlation function analysis and also by an alternative method for estimating the maximum likelihood lag. The lag times strongly correlated with the optical luminosity in the luminosity range of M_V_=-16 to -22 mag, and the regression analysis was performed to obtain the correlation log {Delta}t (days)=-2.11 -0.2 M_V_ assuming {Delta}t{prop.to}L^0.5^, which was theoretically expected. We discuss the possible origins of the intrinsic scatter of the dust lag-luminosity correlation, which was estimated to be approximately 0.13 dex, and we find that the difference of internal extinction and delayed response of changes in lag times to the flux variations could have partly contributed to intrinsic scatter. However, we could not detect any systematic change of the correlation with the subclass of the Seyfert type or the Eddington ratio. Finally, we compare the dust reverberation radius with the near-infrared interferometric radius of the dust torus and the reverberation radius of broad Balmer emission lines. The interferometric radius in the K band was found to be systematically larger than the dust reverberation radius in the same band by the about a factor of two, which could be interpreted by the difference between the flux-weighted radius and response-weighted radius of the innermost dust torus. The reverberation radius of the broad Balmer emission lines was found to be systematically smaller than the dust reverberation radius by about a factor of four to five, which strongly supports the unified scheme of the Seyfert type of active galactic nuclei (AGNs). Moreover, we examined the radius-luminosity correlations for the hard X-ray (14-195 keV) and the [O IV] {lambda}25.89 {mu}m emission-line luminosities, which would be applicable for obscured AGNs.
- ID:
- ivo://CDS.VizieR/J/ApJS/106/399
- Title:
- Seyfert 2 galaxies multiwavelength catalog
- Short Name:
- J/ApJS/106/399
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper is a catalog of Seyfert 2 galaxies observed in the 2-10keV band (339 flux entries). In total, it contains data on 150 objects; for 76 objects, a positive detection is reported, while for the remaining sources, 2{sigma} upper limits to the X-ray emission are given. Most of the data have been collected from the literature over a period starting from 1974 up to the middle of 1995. Accurate searches of literature and databases were performed for all objects, and frequently spectral fits were reevaluated in order to make the data in the catalog uniform and complete. Some unpublished data are also included. For six objects, EXOSAT/ME data have been extracted from the satellite database and analyzed; the 13 fluxes obtained have been added to the present catalog. The compilation of hard X-ray data has been complemented with data in the soft (0.1-3keV) X-ray band, as well as in ultraviolet (1450A), optical (5500A), infrared (3.5, 12, 25, 60, 100mm), and radio (6cm) bands. Fluxes of the [O III] {lambda}5007 and H{beta} emission lines as well as the Balmer decrement H{alpha}/H{beta}, and axial ratio a/b are also given. The present database is meant to be a useful tool for the study of the Seyfert 2 phenomenon in its various aspects.
- ID:
- ivo://CDS.VizieR/J/AJ/126/1750
- Title:
- Seyfert population in SSRS2
- Short Name:
- J/AJ/126/1750
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The magnitude-limited catalog of the Southern Sky Redshift Survey (SSRS2, Cat. <J/AJ/116/1>) is used to characterize the properties of galaxies hosting active galactic nuclei (AGNs). Using emission-line ratios, we identify a total of 162 (3%) Seyfert galaxies out of the parent sample with 5399 galaxies. The sample contains 121 Seyfert 2 galaxies and 41 Seyfert 1 galaxies. The SSRS2 Seyfert galaxies are predominantly in spirals of types Sb and earlier or in galaxies with perturbed appearance as the result of strong interactions or mergers. Seyfert galaxies in this sample are twice as common in barred hosts as the non-Seyfert galaxies. By assigning galaxies to groups using a percolation algorithm, we find that the Seyfert galaxies in the SSRS2 are more likely to be found in binary systems when compared with galaxies in the SSRS2 parent sample. However, there is no statistically significant difference between the Seyfert and SSRS2 parent sample when systems with more than two galaxies are considered. The analysis of the present sample suggests that there is a stronger correlation between the presence of the AGN phenomenon with internal properties of galaxies (morphology, presence of bar, luminosity) than with environmental effects (local galaxy density, group velocity dispersion, nearest neighbor distance).
- ID:
- ivo://CDS.VizieR/J/A+A/335/912
- Title:
- Seyferts in galaxy pairs and groups
- Short Name:
- J/A+A/335/912
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The occurrence of Seyfert galaxies in 6 samples representative of different cosmological environments (i.e. isolated pairs, compact and loose groups) is analysed. To avoid biases linked to subjective sample selection criteria only canonical samples, taken from the literature, are considered. It is found that the average frequency of Seyferts in all samples, is near 2%. Most Seyferts lying in pairs and compact groups show disturbed morphological appearance, whilst in loose groups disturbed and ``isolated'' Seyferts have roughly the same proportion. Then, within each sample, structures which host a Seyfert are compared to structures which do not. No appreciable differences regarding dynamical properties are found.
- ID:
- ivo://CDS.VizieR/J/A+A/643/A127
- Title:
- 5 Seyferts reduced CO(2-1) cubes
- Short Name:
- J/A+A/643/A127
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Active galactic nucleus (AGN) driven outflows are believed to play an important role in regulating the growth of galaxies, mostly via negative feedback. However, their effects on their hosts are far from clear, especially for low- and moderate-luminosity Seyferts. To investigate this issue, we obtained cold molecular gas observations, traced by the CO(2-1) transition, using the NOEMA interferometer of five nearby (distances between 19 and 58Mpc) Seyfert galaxies. The resolution of ~0.3-0.8 (~30-100pc) and field of view of NOEMA allowed us to study the CO(2-1) morphology and kinematics in the nuclear regions (~100pc) and up to radial distances of ~900pc. We detected CO(2-1) emission in all five galaxies with disky or circumnuclear ring-like morphologies. We derived cold molecular gas masses on nuclear (~100pc) and circumnuclear (~650pc) scales in the range from 10^6^ to 10^7^M_{sun}_ and from 10^7^ to 10^8^M_{sun}_, respectively. In all of our galaxies, the bulk of this gas is rotating in the plane of the galaxy. However, noncircular motions are also present. In NGC 4253, NGC 4388, and NGC 7465, we can ascribe the streaming motions to the presence of a large-scale bar. In Mrk 1066 and NGC 4388, the noncircular motions in the nuclear regions are explained as outflowing material due to the interaction of the AGN wind with molecular gas in the galaxy disk. We conclude that for an unambiguous and precise interpretation of the kinematics of the cold molecular gas, we need detailed knowledge of the host galaxy (i.e., presence of bars, interactions, etc.), and also of the ionized gas kinematics and ionization cone geometry.
