- ID:
- ivo://CDS.VizieR/VII/289
- Title:
- SDSS quasar catalog, sixteenth data release (DR16Q)
- Short Name:
- VII/289
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the final Sloan Digital Sky Survey IV (SDSS-IV) quasar catalog from Data Release 16 of the extended Baryon Oscillation Spectroscopic Survey (eBOSS). This catalog comprises the largest selection of spectroscopically confirmed quasars to date. The full catalog includes two subcatalogs (the current versions are DR16Q_v4 and DR16Q_Superset_v3 at http://data.sdss.org/sas/dr16/eboss/qso/DR16Q): a "superset" of all SDSS-IV/eBOSS objects targeted as quasars containing 1,440,615 observations and a quasar-only catalog containing 750,414 quasars, including 225,082 new quasars appearing in an SDSS data release for the first time, as well as known quasars from SDSS-I/II/III. We present automated identification and redshift information for these quasars alongside data from visual inspections for 320,161 spectra. The quasar-only catalog is estimated to be 99.8% complete with 0.3%-1.3% contamination. Automated and visual inspection redshifts are supplemented by redshifts derived via principal component analysis and emission lines. We include emission-line redshifts for H{alpha}, H{beta}, MgII, CIII], CIV, and Ly{alpha}. Identification and key characteristics generated by automated algorithms are presented for 99,856 broad absorption-line quasars and 35,686 damped Lyman alpha quasars. In addition to SDSS photometric data, we also present multiwavelength data for quasars from the Galaxy Evolution Explorer, UKIDSS, the Wide-field Infrared Survey Explorer, FIRST, ROSAT/2RXS, XMM-Newton, and Gaia.
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Search Results
- ID:
- ivo://CDS.VizieR/VII/264
- Title:
- Second Byurakan Survey galaxies. Optical database
- Short Name:
- VII/264
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A database for the entire catalog of the Second Byurakan Survey (SBS) galaxies is presented. It contains new measurements of their optical parameters and additional information taken from the literature and other databases. The measurements were made using Ipg(near-infrared), Fpg(red) and Jpg(blue) band images from photographic sky survey plates obtained by the Palomar Schmidt telescope and extracted from the STScI Digital Sky Survey (DSS). The database provides accurate coordinates, morphological type, spectral and activity classes, apparent magnitudes and diameters, axial ratios, and position angles, as well as number counts of neighboring objects in a circle of radius 50kpc. The total number of individual SBS objects in the database is now 1676. The 188 Markarian galaxies which were re-discovered by SBS are not included in this database. We also include redshifts that are now available for 1576 SBS objects, as well as 2MASS infrared magnitudes for 1117 SBS galaxies.
- ID:
- ivo://CDS.VizieR/VII/276
- Title:
- Second Byurakan Survey. General Catalogue
- Short Name:
- VII/276
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Second Byurakan Survey (SBS) General Catalogue is presented. The SBS, a continuation of the Markarian survey reaching fainter limiting magnitudes, is the first survey which combines the search of galaxies and QSOs. A total area of 991 square degrees of the Northern sky was covered with the use of three objective prisms in combination with Schott filters. The limited magnitude on the best plates reached B~19.5. The General Catalogue consists of 3563 objects presented in two parts: a Catalogue of galaxies (1863 objects) and one of stellar objects (1700 objects). The Catalogue of SBS AGN consists of 761 objects (155 SyG, 596 QSOs, and 10 BLLac). Multi-wavelength data are presented for 1438 SBS objects identified with X-ray, IRAS and FIRST sources. Spectrophotometric observations obtained over 26 years are available for 3132 objects. Redshifts were measured for ~2100 extragalactic objects. Spectral classification is presented for ~2970 objects. The majority of the data is presented here for the first time. The Catalogue presents new large homogeneous deep representative complete samples of bright QSOs, AGNs, and faint UVX galaxies in the Northern sky. The SBS sample is found to be complete at 70% for galaxies and ~85% for AGN/QSOs with B<=17.5.
- ID:
- ivo://CDS.VizieR/J/MNRAS/495/1853
- Title:
- SED-selected AGN in the VIPERS field
- Short Name:
- J/MNRAS/495/1853
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The detection of X-ray emission constitutes a reliable and efficient tool for the selection of active galactic nuclei (AGNs), although it may be biased against the most heavily absorbed AGNs. Simple mid-infrared (IR) broad-band selection criteria identify a large number of luminous and absorbed AGNs, yet again host contamination could lead to non-uniform and incomplete samples. Spectral energy distribution (SED) decomposition is able to decouple the emission from the AGN versus that from star-forming regions, revealing weaker AGN components. We aim to identify the obscured AGN population in the VIMOS Public Extragalactic Redshift Survey in the Canada-France-Hawaii Telescope Legacy Survey W1 field through SED modelling. We construct SEDs for 6860 sources and identify 160 AGNs at a high confidence level using a Bayesian approach. Using optical spectroscopy, we confirm the nature of ~85 per cent of the AGNs. Our AGN sample is highly complete (~92 per cent) compared to mid-IR colour-selected AGNs, including a significant number of galaxy-dominated systems with lower luminosities. In addition to the lack of X-ray emission (80 per cent), the SED fitting results suggest that the majority of the sources are obscured. We use a number of diagnostic criteria in the optical, IR, and X-ray regimes to verify these results. Interestingly, only 35 per cent of the most luminous mid-IR-selected AGNs have X-ray counterparts suggesting strong absorption. Our work emphasizes the importance of using SED decomposition techniques to select a population of type II AGNs, which may remain undetected by either X-ray or IR colour surveys.
- ID:
- ivo://CDS.VizieR/J/MNRAS/464/183
- Title:
- Segregation effects in DEEP2 galaxy groups
- Short Name:
- J/MNRAS/464/183
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We investigate segregation phenomena in galaxy groups in the range of 0.2<z<1. We study a sample of groups selected from the 4th Data Release of the DEEP2 galaxy redshift survey. We used only groups with at least eight members within a radius of 4 Mpc. Outliers were removed with the shifting gapper technique and, then, the virial properties were estimated for each group. The sample was divided into two stacked systems: low(z<=0.6) and high (z>0.6) redshift groups. Assuming that the colour index (U-B)_0_ can be used as a proxy for the galaxy type, we found that the fraction of blue (star-forming) objects is higher in the high-z sample, with blue objects being dominant at M_B_>-19.5 for both samples, and red objects being dominant at M_B_<-19.5 only for the low-z sample. Also, the radial variation of the red fraction indicates that there are more red objects with R<R_200_ in the low-z sample than in the high-z sample. Our analysis indicates statistical evidence of kinematic segregation, at the 99 per cent c.l., for the low-z sample: redder and brighter galaxies present lower velocity dispersions than bluer and fainter ones. We also find a weaker evidence for spatial segregation between red and blue objects, at the 70 per cent c.l. The analysis of the high-z sample reveals a different result: red and blue galaxies have velocity dispersion distributions not statistically distinct, although redder objects are more concentrated than the bluer ones at the 95 per cent c.l. From the comparison of blue/red and bright/faint fractions, and considering the approximate lookback time-scale between the two samples (~3Gyr), our results are consistent with a scenario where bright red galaxies had time to reach energy equipartition, while faint blue/red galaxies in the outskirts infall to the inner parts of the groups, thus reducing spatial segregation from z~0.8 to z~0.4.
- ID:
- ivo://CDS.VizieR/J/A+AS/125/247
- Title:
- Shapley Concentration galaxies velocities
- Short Name:
- J/A+AS/125/247
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report velocity measurements of galaxies in this, the densest mass concentration within z=0.1, obtained with the multifiber spectrograph MEFOS at ESO, La Silla. We derive redshifts of a number of Abell clusters and draw implications for the supercluster structure. The clusters A3554, A3566, A3577 and AS718 are confirmed as members, while the clusters A3524, A3531, A3542, A3545 and A3549 are shown to be background systems and A3581 a foreground one
- ID:
- ivo://CDS.VizieR/J/MNRAS/327/249
- Title:
- SMAC. II. Fundamental Plane photometric data
- Short Name:
- J/MNRAS/327/249
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present new R-band photometric data for 447 galaxies, gathered for the Streaming Motions of Abell Clusters (SMAC) project. The data comprise 629 individual measurements of the Fundamental Plane (FP) parameters effective radius (Re) and surface brightness (<{mu}>_e_), derived from R^1/4^-law profile fitting. More than a third of the galaxies were observed more than once.
- ID:
- ivo://CDS.VizieR/J/MNRAS/327/265
- Title:
- SMAC. III. Fundamental Plane catalog
- Short Name:
- J/MNRAS/327/265
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the construction of a new, standardized all-sky catalogue of Fundamental Plane (FP) data from early-type galaxies in clusters, for peculiar velocity applications. This catalogue is based on a compilation of spectroscopic and photometric data consisting of data reported in previous papers of this series, plus data from published sources.
- ID:
- ivo://CDS.VizieR/J/MNRAS/435/1680
- Title:
- SN Ia host galaxy properties
- Short Name:
- J/MNRAS/435/1680
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We study the stellar populations of Type Ia supernova (SN Ia) host galaxies using Sloan Digital Sky Survey (SDSS)-II spectroscopy. The main focus is on the relationships of SN Ia properties with stellar velocity dispersion and the stellar population parameters age, metallicity and element abundance ratios. We concentrate on a sub-sample of 84 SNe Ia from the SDSS-II Supernova Survey and find that SALT2 stretch factor values show the strongest dependence on stellar population age. Hence, more luminous SNe Ia appear in younger stellar progenitor systems. No statistically significant trends in the Hubble residual with any of the stellar population parameters studied are found. Moreover, the method of photometric stellar mass derivation affects the Hubble residual-mass relationship. For an extended sample (247 objects), including SNe Ia with SDSS host galaxy photometry only, the Hubble residual-mass relationship behaves as a sloped step function. In the high-mass regime, probed by our host spectroscopy sample, this relationship is flat. Below a stellar mass of ~2x10^10^M_{sun}_, i.e. close to the evolutionary transition mass of low-redshift galaxies, the trend changes dramatically such that lower mass galaxies possess lower luminosity SNe Ia after light-curve corrections. The sloped step function of the Hubble residual-mass relationship should be accounted for when using stellar mass as a further parameter for minimizing the Hubble residuals.
- ID:
- ivo://CDS.VizieR/J/MNRAS/445/2440
- Title:
- SN with associated Planck CMB temperatures
- Short Name:
- J/MNRAS/445/2440
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- By using the Planck map of the cosmic microwave background (CMB) radiation, we have checked and confirmed the existence of a correlation between supernova (SN) redshifts, z_SN_, and CMB temperature fluctuations at the SNe locations, T_SN_, which we previously reported for the Wilkinson Microwave Anisotropy Probe data. The Pearson correlation coefficient for the Planck data is r=+0.38+/-0.08, which indicates that the correlation is statistically significant (the signal is about 5{sigma} above the noise level). The correlation becomes even stronger for the Type Ia subsample of SNe, r_Ia_=+0.45+/-0.09, whereas for the rest of the SNe it is vanishing. By checking the slopes of the regression lines T_SN_/z_SN_ for Planck's different frequency bands, we have also excluded the possibility of this anomaly being caused by the Sunyaev-Zeldovich effect. The remaining possibility is some, unaccounted for, contribution to the CMB from distant (z>0.3) foreground through either the integrated Sachs-Wolfe effect or thermal emission from intergalactic matter.
