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- ID:
- ivo://CDS.VizieR/VII/248
- Title:
- Quasars and Active Galactic Nuclei (12th Ed.)
- Short Name:
- VII/248
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalogue is an update of the previous versions; as in the previous editions no information about absorption lines of X-ray properties are given, but absolute magnitudes are given, assuming Ho=50km/s/Mpc and q_0_=0. In this edition the 20cm radio flux is listed when available, in place of the 11cm flux. The present edition of this catalogue contains the quasars with measured redshift known prior to January 1st, 2006. It contains 85221 quasars, 1122 BL Lac objects and 21737 active galaxies (including 9628 Seyfert 1s), almost doubling the number listed in the 11th edition. Lists of known lensed quasars (table2.dat) and double quasars (table3.dat) are also given here.
- ID:
- ivo://CDS.VizieR/VII/258
- Title:
- Quasars and Active Galactic Nuclei (13th Ed.)
- Short Name:
- VII/258
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalogue is a compilation of all known AGNs presented in a compact and convenient form. It is an update of the previous versions; and as in the previous editions no information about absorption lines of X-ray properties are given, but absolute magnitudes are given, assuming Ho=71km/s/Mpc and q_0_=0 (notice the change of cosmology: Ho was assumed to be 50km/s/Mpc in the previous editions). When available, the 20cm and 6cm radio flux are given. The present edition of this catalogue contains the quasars with measured redshift known prior to July 1st, 2009. It contains 133336 quasars, 1374 BL Lac objects and 34231 active galaxies (including 15627 Seyfert 1's), almost doubling the number listed in the 12th edition. Lists of known lensed quasars (table2.dat) and double quasars (table3.dat) are also given here.
- ID:
- ivo://CDS.VizieR/VII/215
- Title:
- Quasars and Active Galactic Nuclei (9th Ed.)
- Short Name:
- VII/215
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalogue is an update of the previous versions. It contains 13214 (+1856) quasars (defined as brighter than absolute B magnitude -23), 4428 (+1094) AGNs (defined as fainter than absolute B magnitude -23) and 462 (+105) BL Lac objects from 2054 (+191) references.
- ID:
- ivo://CDS.VizieR/VII/224
- Title:
- Quasars and Active Galactic Nuclei (10th Ed.)
- Short Name:
- VII/224
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalogue is an update of the previous versions. The recent publication of the first release of the 2dF quasar survey (Croom et al., 2001MNRAS.322L..29C, see Cat. <VII/223>) containing nearly 10,000 new QSOs, almost doubled the number of known such objects: there are now 23760 (+10546) quasars (defined as brighter than absolute B magnitude -23), 5751 (+1323) AGNs (defined as fainter than absolute B magnitude -23) of which 2765 are Seyfert 1, and 608 (+146) BL Lac objects from 2173 (+119) references. Like the ninth edition, it includes position and redshift as well as photometry (U, B, V) and 6 and 11 cm flux densities when available. The present edition this catalogue contains the quasars with measured redshift known prior to May 1st, 2001.
- ID:
- ivo://CDS.VizieR/VII/207
- Title:
- Quasars and Active Galactic Nuclei (8th Ed.)
- Short Name:
- VII/207
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalogue is an update of the previous versions. It contains 11358 (+2759) quasars (defined as brighter than absolute B magnitude -23), 3334 (+501) AGNs (defined as fainter than absolute B magnitude -23) and 357 (+137) BL Lac objects from 1863 (+201) references.
- ID:
- ivo://CDS.VizieR/J/A+A/642/A150
- Title:
- Quasars as standard candles. III.
- Short Name:
- J/A+A/642/A150
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a new catalogue of ~2400 optically selected quasars with spectroscopic redshifts and X-ray observations from either Chandra or XMM-Newton. The sample can be used to investigate the non-linear relation between the UV and X-ray luminosity of quasars, and to build a Hubble diagram up to redshift z~7.5. We selected sources that are neither reddened by dust in the optical/UV nor obscured by gas in the X-rays, and whose X-ray fluxes are free from flux-limit related biases. After checking for any possible systematics, we confirm, in agreement with our previous works, that (i) the X-ray to UV relation provides distance estimates matching those from supernovae up to z~1.5, and (ii) its slope shows no redshift evolution up to z~5. We provide a full description of the methodology for testing cosmological models, further supporting a trend whereby the Hubble diagram of quasars is well reproduced by the standard flat LambdaCDM model up to z~1.5-2, but strong deviations emerge at higher redshifts. Since we have minimized all non-negligible systematic effects, and proven the stability of the Lx-Lo relation at high redshifts, we conclude that an evolution of the expansion rate of the Universe should be considered as a possible explanation for the observed deviation, rather than some systematic (redshift-dependent) effect associated with high-redshift quasars.
- ID:
- ivo://CDS.VizieR/J/ApJ/801/45
- Title:
- Quasars properties and reverberation mapping
- Short Name:
- J/ApJ/801/45
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We explore the practical feasibility of active galactic nucleus (AGN) broadband reverberation mapping and present first results. We lay out and apply a rigorous approach for the stochastic reverberation mapping of unevenly sampled multi-broadband flux measurements, assuming that the broad-line region (BLR) line flux is contributing up to 15% in some bands, and is directly constrained by one spectroscopical epoch. The approach describes variations of the observed flux as the continuum, modeled as a stochastic Gaussian process, and emission line contribution, modeled as a scaled, smoothed, and delayed version of the continuum. This approach can be used not only to interpolate in time between measurements, but also to determine confidence limits on continuum-line emission delays. This approach is applied to Sloan Digital Sky Survey observations in Stripe 82 (S82), providing flux measurements that are precise to 2% at ~60 epochs over ~10 yr. The strong annual variations in the epoch sampling prove a serious limitation in practice. In addition, suitable redshift ranges must be identified where strong, broad emission lines contribute to one filter, but not to another. By generating and evaluating problem-specific mock data, we verify that S82-like data can constrain {tau}_delay_ for a simple transfer function model. In application to real data, we estimate {tau}_delay_ for 323 AGNs with 0.225<z<0.846, combining information for different objects through the ensemble-scaling relationships for BLR size and black hole mass. Our analysis tentatively indicates a 1.7 times larger BLR size of H{alpha} and Mg II compared to Kaspi et al. (2000ApJ...533..631K; 2007ApJ...659..997K) and Vestergaard (2002ApJ...571..733V; 2006ApJ...641..689V), but the seasonal data sampling casts doubt on the robustness of the inference.
- ID:
- ivo://CDS.VizieR/J/MNRAS/445/955
- Title:
- Radio-AGN feedback for 0.5<z<1
- Short Name:
- J/MNRAS/445/955
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper presents the first measurement of the radio luminosity function of 'jet-mode' (radiatively inefficient) radio-AGN out to z=1, in order to investigate the cosmic evolution of radio-AGN feedback. Eight radio source samples are combined to produce a catalogue of 211 radio-loud AGN with 0.5<z<1.0, which are spectroscopically classified into jet-mode and radiative-mode (radiatively efficient) AGN classes. Comparing with large samples of local radio-AGN from the Sloan Digital Sky Survey, the cosmic evolution of the radio luminosity function of each radio-AGN class is independently derived. Radiative-mode radio-AGN show an order of magnitude increase in space density out to z~1 at all luminosities, consistent with these AGN being fuelled by cold gas. In contrast, the space density of jet-mode radio-AGN decreases with increasing redshift at low radio luminosities (L_1.4GHz_<~10^24^W/Hz) but increases at higher radio luminosities. Simple models are developed to explain the observed evolution. In the best-fitting models, the characteristic space density of jet-mode AGN declines with redshift in accordance with the declining space density of massive quiescent galaxies, which fuel them via cooling of gas in their hot haloes. A time delay of 1.5-2Gyr may be present between the quenching of star formation and the onset of jet-mode radio-AGN activity. The behaviour at higher radio luminosities can be explained either by an increasing characteristic luminosity of jet-mode radio-AGN activity with redshift (roughly as (1+z)^3^) or if the jet-mode radio-AGN population also includes some contribution of cold-gas-fuelled sources seen at a time when their accretion rate was low. Higher redshifts measurements would distinguish between these possibilities.
- ID:
- ivo://CDS.VizieR/J/MNRAS/347/837
- Title:
- Radio and K-band obs. of Ultra-Steep sources
- Short Name:
- J/MNRAS/347/837
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A sample of 76 ultra-steep spectrum (USS) radio sources is defined from the 843-MHz Sydney University Molonglo Sky Survey (SUMSS) and 1.4-GHz NRAO VLA Sky Survey (NVSS) radio surveys with spectral index {alpha}<-1.3 and S(1.4GHz)>15mJy; 71 of these sources without bright optical or near-infrared counterparts at 1.385GHz were observed with the Australia Telescope Compact Array (ATCA), providing 5arcsec resolution images and subarcsec positional accuracy. To identify their host galaxies, near-infrared K-band images were obtained with IRIS2 at the AAT and SofI at the NTT; 92% of the USS sources could be identified down to K~20.5. 142 FITS files containing the radio maps and the K-band images are included in the fits subdirectory.
