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121. Catalog of galaxies around PKS 0405-123
ID:
ivo://CDS.VizieR/J/MNRAS/434/1765
Title:
Catalog of galaxies around PKS 0405-123
Short Name:
J/MNRAS/434/1765
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present new absorption-line analysis and new galaxy survey data obtained for the field around PKS 0405-123 at z_QSO_=0.57. Combining previously known OVI absorbers with new identifications in the higher S/N ultraviolet (UV) spectra obtained with the Cosmic Origins Spectrograph, we have established a sample of 7 OVI absorbers and 12 individual components at z=0.0918-0.495 along the sightline towards PKS 0405-123. We complement the available UV absorption spectra with galaxy survey data that reach 100 percent completeness at projected distances {rho}<200kpc of the quasar sightline for galaxies as faint as 0.1L* (0.2L*) out to redshifts of z~0.35 (z~0.5). The high level of completeness achieved at faint magnitudes by our survey reveals that OVI absorbers are closely associated with gas-rich environments containing at least one low-mass, emission-line galaxy. An intriguing exception is a strong OVI system at z~0.183 that does not have a galaxy found at {rho}<4Mpc, and our survey rules out the presence of any galaxies of L>0.04L* at {rho}<250kpc and any galaxies of L>0.3L* at {rho}<1Mpc. We further examine the galactic environments of OVI absorbers and those 'Ly{alpha}-only' absorbers with neutral hydrogen column density log N(HI)<13.6 and no detectable OVI absorption features. The Ly{alpha}-only absorbers serve as a control sample in seeking the discriminating galactic features that result in the observed Ovi absorbing gas at large galactic radii. We find a clear distinction in the radial profiles of mean galaxy surface brightness around different absorbers. Specifically, Ovi absorbers are found to reside in regions of higher mean surface brightness at {rho}<~500kpc ({Delta}{mu}_R_~+5magMpc^-2^ relative to the background at {rho}>500kpc), while only a mild increase in galaxy surface brightness is seen at small {rho} around Ly{alpha}-only absorbers ({Delta}{mu}_R_~+2magMpc^-2^). The additional insights gained from our deep galaxy survey demonstrate the need to probe the galaxy populations to low luminosities in order to better understand the nature of the absorbing systems.
122. Catalog of SDSS-DR5/2MASS spectroscopic quasars
ID:
ivo://CDS.VizieR/J/MNRAS/382/412
Title:
Catalog of SDSS-DR5/2MASS spectroscopic quasars
Short Name:
J/MNRAS/382/412
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a catalog of 13444 SDSS-DR5 spectroscopic quasars which have an 2MASS near-IR counterpart within 5" of their position.
123. Catalog of strong MgII absorbers
ID:
ivo://CDS.VizieR/J/A+A/546/A67
Title:
Catalog of strong MgII absorbers
Short Name:
J/A+A/546/A67
Date:
21 Oct 2021
Publisher:
CDS
Description:
A significantly higher incidence of strong (rest equivalent width Wr>1{AA}) intervening MgII absorption is observed along gamma-ray burst (GRB) sight-lines relative to those of quasar sight-lines. A geometrical explanation for this discrepancy has been suggested: the ratio of the beam size of the source to the characteristic size of an MgII absorption system can influence the observed MgII equivalent width, if these two sizes are comparable. We investigate whether the differing beam sizes of the continuum source and broad-line region of Sloan Digital Sky Survey (SDSS) quasars produce a discrepancy between the incidence of strong MgII absorbers illuminated by the quasar continuum region and those of absorbers illuminated by both continuum and broad-line region light.
124. Catalog of variability selected AGNs in GOODS
ID:
ivo://CDS.VizieR/J/ApJ/723/737
Title:
Catalog of variability selected AGNs in GOODS
Short Name:
J/ApJ/723/737
Date:
21 Oct 2021
Publisher:
CDS
Description:
Variability is a property shared by practically all active galactic nuclei (AGNs). This makes variability selection a possible technique for identifying AGNs. Given that variability selection makes no prior assumption about spectral properties, it is a powerful technique for detecting both low-luminosity AGNs in which the host galaxy emission is dominating and AGNs with unusual spectral properties. In this paper, we will discuss and test different statistical methods for the detection of variability in sparsely sampled data that allow full control over the false positive rates. We will apply these methods to the GOODS North and South fields and present a catalog of variable sources in the z band in both GOODS fields. Out of the 11 931 objects checked, we find 155 variable sources at a significance level of 99.9%, corresponding to about 1.3% of all objects. After rejection of stars and supernovae, 139 variability-selected AGNs remain. Their magnitudes reach down as faint as 25.5mag in z. Spectroscopic redshifts are available for 22 of the variability-selected AGNs, ranging from 0.046 to 3.7. The absolute magnitudes in the rest-frame z band range from ~-18 to -24, reaching substantially fainter than the typical luminosities probed by traditional X-ray and spectroscopic AGN selection in these fields. Therefore, this is a powerful technique for future exploration of the evolution of the faint end of the AGN luminosity function up to high redshifts.
125. Catalog Quasars and Active Galactic Nuclei
ID:
ivo://jvo/agn
Title:
Catalog Quasars and Active Galactic Nuclei
Short Name:
AGN
Date:
14 Nov 2019 03:45:31
Publisher:
JVO
Description:
A collection of QSO and AGN catalogs.
127. Catalogue of 1806 MgII absorbers from SDSS DR3
ID:
ivo://CDS.VizieR/J/MNRAS/371/495
Title:
Catalogue of 1806 MgII absorbers from SDSS DR3
Short Name:
J/MNRAS/371/495
Date:
21 Oct 2021
Publisher:
CDS
Description:
We measure the mean halo mass of z=~0.5 MgII absorbers using the cross-correlation (over comoving scales 0.05-13h^-1^Mpc) between 1806 MgII quasar absorption systems and ~250000 luminous red galaxies (LRGs), both selected from the Sloan Digital Sky Survey Data Release 3.
128. Catalogue of quasar candidates
ID:
ivo://CDS.VizieR/J/MNRAS/247/182
Title:
Catalogue of quasar candidates
Short Name:
J/MNRAS/247/182
Date:
21 Oct 2021
Publisher:
CDS
Description:
This paper gives a list of all quasar candidates obtained from an automated computer search performed on 11 grens plates. The description of the main characteristics of the survey is given along with the latest improvements in the selection techniques. Particular attention has been paid to understanding and quantifying selection effects. This allows the construction of homogeneous samples having well-understood characteristics. The noteworthy aspect of our homogenization process is the correction that we apply to our probability classes in order to take into account the signal-to-noise differences; at a given magnitude, among plates of different limiting magnitudes. Since such homogeneous material is rare, this catalogue is of general interest. Each grens plate covers about 1 square degree with typical limiting magnitude of B~21. Data are given with all relevant quantities needed to understand the characteristics of the survey. We expect that over 100 of the 125 higher probability class candidates are quasars. A third of the ~400 lower probability objects should also be quasars. This material is well-suited to follow-up spectroscopy with fibre spectrographs.
129. Catching the radio flare in CTA 102
ID:
ivo://CDS.VizieR/J/A+A/551/A32
Title:
Catching the radio flare in CTA 102
Short Name:
J/A+A/551/A32
Date:
21 Oct 2021
Publisher:
CDS
Description:
Very Long Baseline Interferometry (VLBI) observations can resolve the radio structure of active galactic nuclei (AGN) and provide estimates of the structural and kinematic characteristics on parsec-scales in their jets. The changes in the kinematics of the observed jet features can be used to study the physical conditions in the innermost regions of these sources. We performed multifrequency multiepoch Very Long Baseline Array (VLBA) observations of the blazar CTA102 during its 2006 radio flare, the strongest ever reported for this source. These observations provide an excellent opportunity to investigate the evolution of the physical properties of blazars, especially during these flaring events. We want to study the kinematic changes in the source during the strong radio outburst in April 2006 and test the assumption of a shock-shock interaction. This assumption is based on the analysis and modeling of the single-dish observations of CTA 102 (Paper I, 2011A&A...531A..95F). In this paper we study the kinematics of CTA 102 at several frequencies using VLBI observations. From the modeled jet features we derived estimates for the evolution of the physical parameters, such as the particle density and the magnetic field. Furthermore ,we combined our observations during the 2006 flare with long-term VLBA monitoring of the source at 15 GHz and 43 GHz We cross-identified seven features throughout our entire multifrequency observations and find evidence of two possible recollimation shocks around 0.1mas (deprojected 18pc at a viewing angle of 2.6{deg} and 6.0mas (deprojected 1kpc) from the core. The 43GHz observations reveal a feature ejected at epoch t_ej_=2005.9+/-0.2, which could be connected to the 2006 April radio flare. Furthermore, this feature might be associated with the traveling component involved in the possible shock-shock interaction, which gives rise to the observed double peak structure in the single-dish light curves reported in Paper I, 2011A&A...531A..95F.
130. Celestial Reference Frame at 24 and 43 GHz
ID:
ivo://CDS.VizieR/J/AJ/139/1695
Title:
Celestial Reference Frame at 24 and 43 GHz
Short Name:
J/AJ/139/1695
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present astrometric results for compact extragalactic objects observed with the Very Long Baseline Array at radio frequencies of 24 and 43GHz. Data were obtained from ten 24-hr observing sessions made over a five-year period. These observations were motivated by the need to extend the International Celestial Reference Frame (ICRF) to higher radio frequencies to enable improved deep space navigation after 2016 and to improve state-of-the-art astrometry. Source coordinates for 268 sources were estimated at 24GHz and for 131 sources at 43GHz.

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