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81. Allsky cross-matched 3XMMe catalogue
ID:
ivo://CDS.VizieR/IX/48
Title:
Allsky cross-matched 3XMMe catalogue
Short Name:
IX/48
Date:
21 Oct 2021
Publisher:
CDS
Description:
ARCHES (Astronomical Resource Cross-matching for High Energy Studies) is a FP7-Space funded project whose aim is to provide the astronomical community with well-characterised multi-wavelength data in the form of spectral energy distributions (SEDs) for large samples of objects extracted from the 3XMM DR5 X-ray catalogue of serendipitous sources. The project has developed new tools implementing fully probabilistic simultaneous cross-correlation of several catalogues for unresolved sources. A cleaned and enhanced version of the 3XMM DR5 catalogue (the 3XMMe catalogue) has been cross-correlated using the ARCHES tool with a number of selected multi-wavelength archival catalogues. These catalogues cover wavelengths ranging from UV to far IR. They provide probabilities of associations, magnitude and fluxes from which spectral energy distributions can be extracted.
82. All-Sky Survey of Flat-Spectrum Radio Sources
ID:
ivo://CDS.VizieR/J/ApJS/171/61
Title:
All-Sky Survey of Flat-Spectrum Radio Sources
Short Name:
J/ApJS/171/61
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have assembled an 8.4GHz survey of bright, flat-spectrum ({alpha}>-0.5) radio sources with nearly uniform extragalactic (|b|>10{deg}) coverage for sources brighter than S_4.8GHz_=65mJy. The catalog is assembled from existing observations (especially CLASS and the Wright et al., Cat VIII/38, PMN-CA survey), augmented by reprocessing of archival VLA and ATCA data and by new observations to fill in coverage gaps. We refer to this program as CRATES, the Combined Radio All-Sky Targeted Eight GHz Survey. The resulting catalog provides precise positions, subarcsecond structures, and spectral indices for some 11000 sources. We describe the morphology and spectral index distribution of the sample and comment on the survey's power to select several classes of interesting sources, especially high-energy blazars. Comparison of CRATES with other high-frequency surveys also provides unique opportunities for identification of high-power radio sources.
83. A low-luminosity type-1 QSO sample. III.
ID:
ivo://CDS.VizieR/J/A+A/580/A113
Title:
A low-luminosity type-1 QSO sample. III.
Short Name:
J/A+A/580/A113
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report on the optical spectroscopic analysis of a sample of 99 low-luminosity quasi-stellar objects (LLQSOs) at z<=0.06 base the Hamburg/ESO QSO Survey (HES). To better relate the low-redshift active galactic nucleus (AGN) to the QSO population it is important to study samples of the latter type at a level of detail similar to that of the low-redshift AGN. Powerful QSOs, however, are absent at low redshifts due to evolutionary effects and their small space density. Our understanding of the (distant) QSO population is, therefore, significantly limited by angular resolution and sensitivity. The LLQSOs presented here offer the possibility of studying the faint end of this population at smaller cosmological distances and, therefore, in greater detail. In comparing two spectroscopic methods, we aim to establish a reliable activity classification scheme of the LLQSOs sample. Our goal is to enrich our systematic multiwavelength analysis of the AGN/starburst relation in these systems and give a complementary information on this particular sample of LLQSOs from the Hamburg ESO survey. Here, we present results of the analysis of visible wavelength spectroscopy provided by the HES and the 6 Degree Field Galaxy Survey (6dFGS). These surveys use different spectroscopic techniques, long-slit and circular fiber, respectively. These allow us to assess the influence of different apertures on the activity of the LLQSOs using classical optical diagnostic diagrams. We perform a Gaussian fitting of strong optical emission lines and decompose narrow and broad Balmer components. A small number of our LLQSO present no broad component, which is likely to be present but buried in the noise. Two sources show double broad components, whereas six comply with the classic NLS1 requirements. As expected in NLR of broad line AGNs, the [SII]-based electron density values range between 100 and 1000N_e_/cm^3^. Using the optical characteristics of Populations A and B, we find that 50% of our sources with H{beta} broad emission are consistent with the radio-quiet sources definition. The remaining sources could be interpreted as low-luminosity radio-loud quasar. The BPT-based classification renders an AGN/Seyfert activity between 50 to 60%. For the remaining sources, the possible starburst contribution might control the LINER and HII classification. Finally, we discuss the aperture effect as responsible for the differences found between data sets, although variability in the BLR could play a significant role as well.
84. AMIGA XI. Optical nuclear activity
ID:
ivo://CDS.VizieR/J/A+A/545/A15
Title:
AMIGA XI. Optical nuclear activity
Short Name:
J/A+A/545/A15
Date:
21 Oct 2021
Publisher:
CDS
Description:
This study was performe within the frame of the AMIGA project (http://amiga.iaa.es/). We obtained spectral data from the 6th Data Release of the Sloan Digital Sky Survey, which were inspected in a semi-automatic way. We subtracted the underlying stellar populations from the spectra (using the software Starlight) and modelled the nuclear emission features. Standard emission-line diagnostics diagrams were applied, using a new classification scheme that takes into account censored data, to classify the type of nuclear emission. We provide a final catalogue of spectroscopic data, stellar populations, emission lines and classification of optical nuclear activity for AMIGA galaxies. The prevalence of optical active galactic nuclei (AGN) in AMIGA galaxies is 20.4%, or 36.7% including transition objects. The fraction of AGN increases steeply towards earlier morphological types and higher luminosities. We compare these results with a matched analysis of galaxies in isolated denser environments (Hickson Compact Groups). After correcting for the effects of the morphology and luminosity, we find that there is no evidence for a difference in the prevalence of AGN between isolated and compact group galaxies, and we discuss the implications of this result. We find that a major interaction is not a necessary condition for the triggering of optical AGN.
85. A 3mm molecular line survey of NGC1068
ID:
ivo://CDS.VizieR/J/A+A/549/A39
Title:
A 3mm molecular line survey of NGC1068
Short Name:
J/A+A/549/A39
Date:
21 Oct 2021
Publisher:
CDS
Description:
We study the molecular composition of the interstellar medium (ISM) surrounding an active galactic nucleus (AGN), by making an inventory of molecular species and their abundances, to establish a chemical differentiation between starburst galaxies and AGN. We used the IRAM-30m telescope to observe the central 1.5-2kpc region of NGC 1068, covering the frequencies between 86.2GHz and 115.6GHz. Using Boltzmann diagrams, we calculated the column densities of the detected molecules. We used a chemical model to reproduce the abundances found in the AGN, to determine the origin of each detected species, and to test the influence of UV fields, cosmic rays, and shocks on the ISM.
86. A 3.5mm polarimetric survey of radio-loud AGNs
ID:
ivo://CDS.VizieR/J/ApJS/189/1
Title:
A 3.5mm polarimetric survey of radio-loud AGNs
Short Name:
J/ApJS/189/1
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the results from the first large (>100 sources) 3.5mm polarimetric survey of radio-loud active galactic nuclei (AGNs). This wavelength is favorable within the radio-millimeter range for measuring the intrinsic linearly polarized emission from AGNs, since in general it is only marginally affected by Faraday rotation of the electric vector position angle and depolarization. The I, Q, U, and V Stokes parameter observations were performed with the XPOL polarimeter at the IRAM 30m Telescope on different observing epochs from 2005 July (when most of the measurements were made) to 2009 October. Our sample consists of 145 flat-radio-spectrum AGNs with declination >-30{deg} (J2000.0) and flux density >~1Jy at ~86GHz, as measured at the IRAM 30m Telescope from 1978 to 1994. This constraint on the radio spectrum causes our sample to be dominated by blazars, which allows us to conduct new statistical studies on this class of high-luminosity, relativistically beamed emitters. Over our entire source sample, the luminosity of the jets is anticorrelated with the degree of linear polarization. Consistent with previous findings claiming larger Doppler factors for brighter {gamma}-ray blazars, quasars listed in our sample, and in the Fermi Large Area Telescope Bright Source Catalog (LBAS, Abdo et al., 2009ApJ...700..597A), show larger luminosities than non-LBAS ones, but our data do not allow us to confirm the same for BL Lac objects. Our new data can be used to estimate the 3.5mm AGN contribution to measurements of the linear polarization of the cosmic microwave background, such as those performed by the Planck satellite.
87. AMUSING++ nearby galaxy compilation. I. Sample
ID:
ivo://CDS.VizieR/J/AJ/159/167
Title:
AMUSING++ nearby galaxy compilation. I. Sample
Short Name:
J/AJ/159/167
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present here the All-weather MUse Supernova Integral-field of Nearby Galaxies (AMUSING++): the largest compilation of nearby galaxies observed with the Multi Unit Spectroscopic Explorer (MUSE) integral-field spectrograph so far. This collection consists of 635 galaxies from different MUSE projects covering the redshift interval 0.0002<z<0.1. The sample and its main properties are characterized and described here. It includes galaxies of almost all morphological types, with a good coverage in its color-magnitude diagram, within the stellar mass range between 10^8^ and 10^12^M{sun}, and with properties resembling those of a diameter-selected sample. The AMUSING++ sample is, therefore, suitable for studying, with unprecedented detail, the properties of nearby galaxies at global and local scales, providing us with more than 50 million individual spectra. We use this compilation to investigate the presence of galactic outflows. We exploit the use of combined emission-line images to explore the shape of the different ionized components and the distribution along classical diagnostic diagrams to disentangle the different ionizing sources across the optical extension of each galaxy. We use the cross-correlation function to estimate the level of symmetry of the emission lines as an indication of the presence of shocks and/or active galactic nuclei. We uncovered a total of 54 outflows, comprising ~8% of the sample. A large number of the discovered outflows correspond to those driven by active galactic nuclei (~60%), suggesting some bias in the selection of our sample. No clear evidence was found that outflow host galaxies are highly star-forming, and outflows appear to be found within all galaxies around the star-formation sequence.
88. Analysis of broad-line regions in AGNs
ID:
ivo://CDS.VizieR/J/ApJ/700/1173
Title:
Analysis of broad-line regions in AGNs
Short Name:
J/ApJ/700/1173
Date:
21 Oct 2021
Publisher:
CDS
Description:
A two-component model for the broad-line region (BLR) of active galactic nuclei (AGNs) has been suggested for many years but not widely accepted. This model indicates that the broad line can be described with the superposition of two Gaussian components (very broad Gaussian component (VBGC) and intermediate Gaussian component (IMGC)) which are from two physically distinct regions, i.e., very broad line region (VBLR) and intermediate line region. We select a Sloan Digital Sky Survey sample to further confirm this model and give a detailed analysis of the geometry, density, and evolution of these two regions.
89. 6 and 20cm flux densities of radio galaxies
ID:
ivo://CDS.VizieR/J/A+A/342/378
Title:
6 and 20cm flux densities of radio galaxies
Short Name:
J/A+A/342/378
Date:
21 Oct 2021
Publisher:
CDS
Description:
We discuss the "angular size-redshift" relation for compact radio sources distributed over a wide range of redshifts 0.011<=z<=4.72. Our study is based on a sample of 330 5 GHz VLBI contour maps taken from the literature. Unlike extended source samples, the "angular size - redshift" relation for compact radio sources appears consistent with the predictions of standard Friedmann world models with q_0_=~0.5 without the need to consider evolutionary or selection effects due to a "linear size-luminosity" dependence. By confining our analysis to sources having a spectral index, -0.38<={alpha}<=0.18, and a total radio luminosity, Lh^2^>= 10^26^W/Hz (H_0_=100hkm/s/Mpc, q_0_=0.5 used as a numerical example), we are able to restrict the dispersion in the "angular size-redshift" relation. The best fitting regression analysis in the framework of the Friedmann-Robertson-Walker model gives the value of the deceleration parameter q_0_=0.21+/-0.30 if there are no evolutionary or selection effects due to a "linear size-luminosity", "linear size-redshift" or "linear size-spectral index" dependence.
90. 4.85 and 10.45GHz fluxes of SDSS-FIRST sources
ID:
ivo://CDS.VizieR/J/A+A/630/A83
Title:
4.85 and 10.45GHz fluxes of SDSS-FIRST sources
Short Name:
J/A+A/630/A83
Date:
21 Oct 2021
Publisher:
CDS
Description:
A detailed understanding of how the activity of a galactic nucleus regulates the growth of its host is still missing. To understand the activity and the types of accretion of supermassive black holes in different hosts, it is essential to study radio-optical properties of a large sample of extragalactic sources. In particular, we aim at studying the radio spectral index trends across the optical emission line diagnostic diagrams to search for potential (anti)correlations. To this goal, we combine flux densities from the radio FIRST survey at 1.4GHz (with the flux density range 10mJy<=F1.4<=1000mJy for 209 SDSS sources at intermediate redshift (0.04<=z<=0.4) with the Effelsberg radiotelescope measurements at 4.85GHz and 10.45GHz. The information about the optical emission-line ratios is obtained from the SDSS-DR7 catalogue. Using the Effelsberg data, we were able to infer the two-point radio spectral index distributions for star-forming galaxies, composite galaxies (with a combined contribution to the line emission from the star-formation and AGN activity), Seyferts, and low ionization narrow emission region (LINER) galaxies. While studying the distribution of steep, flat, and inverted sources across optical diagnostic diagrams, we found three distinct classes of radio emitters for our sample: (i) sources with steep radio index, high ionization ratio and high radio loudness, (ii) sources with flat radio index, lower ionization ratio and intermediate radio loudness, (iii) sources with inverted radio index, low ionization ratio and low radio loudness. The classes (i), (ii), (iii) cluster mainly along the transition from Seyfert to LINER sources in the BPT diagram. We interpret these groups as a result of the recurrent nuclear-jet activity.