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911. Turin-SyCAT, Seyferts multifrequency catalog
ID:
ivo://CDS.VizieR/J/A+A/659/A32
Title:
Turin-SyCAT, Seyferts multifrequency catalog
Short Name:
J/A+A/659/A32
Date:
02 Mar 2022 06:48:51
Publisher:
CDS
Description:
We present the first release of Turin-SyCAT, a multifrequency catalog of Seyfert galaxies. We selected Seyfert galaxies considering criteria based on radio, infrared, and optical properties and starting from sources belonging to hard X-ray catalogs and surveys. We visually inspected optical spectra available for all selected sources. We adopted homogeneous and stringent criteria in the source selection aiming at reducing the possible contamination from other source classes. Our final catalog includes 351 Seyfert galaxies distinguished in 233 type 1 and 118 type 2. Type 1 Seyfert galaxies appear to have mid-IR colors similar to blazars, but are distinguished from them by their radio-loudness. Additionally, Seyfert 2 galaxies have mid-IR colors more similar to quasars than BL Lac objects. As expected from their spectral properties, type 1 and 2 Seyfert galaxies show a clear distinction when using the u-r color. Finally, we found a tight correlation between the mid-IR fluxes at both 12 and 22 um (i.e., F12 and F22, respectively) and hard X-ray fluxes between 15 and 150 keV. Both Seyfert types appear to follow the same trend and share similar values of the ratios of F12 and F22 to FHX in agreement with expectations of the AGN unification scenario. As future perspectives, the Turin-SyCAT will then be used to search for heavily obscured Seyfert galaxies among unidentified hard X-ray sources, given the correlation between mid-IR and hard X-rays, and to investigate their large-scale environments.
912. UBVRI photometry of FKSZ stars
ID:
ivo://CDS.VizieR/J/A+AS/100/489
Title:
UBVRI photometry of FKSZ stars
Short Name:
J/A+AS/100/489
Date:
21 Oct 2021
Publisher:
CDS
Description:
UBVRI photometry in the Kron-Cousins system was observed for 117 stars of the Catalogue of Fundamental Faint Stars (FKSZ stars) in the declination zone 0 to +18{deg}. The observations were made in 24 nights from July 1988 to March 1989 with the European Southern Observatory (ESO) 0.50m telescope at La Silla, Chile.
913. UBVRI Standard Stars
ID:
ivo://CDS.VizieR/J/AJ/133/2502
Title:
UBVRI Standard Stars
Short Name:
J/AJ/133/2502
Date:
21 Oct 2021
Publisher:
CDS
Description:
UBVRI photoelectric observations have been made of 109 stars around the sky, centered more or less at -50{deg} declination. The majority of the stars fall in the magnitude range 10.4<V<15.5 and in the color index range -0.33<(B-V)<+1.66. These new broadband photometric standard stars average 16.4 measurements each from data taken on 116 different nights over a period of 4yr. Similar data are tabulated for 19 stars of interest that were not observed often enough to make them well-defined standard stars.
914. UCAC4 Catalogue (Zacharias+, 2012)
ID:
ivo://astronet.ru/cas/ucac4
Title:
UCAC4 Catalogue (Zacharias+, 2012)
Short Name:
ucac4
Date:
17 Jun 2006 18:44:05
Publisher:
Sternberg Astronomical Institute Virtual Observatory Project
Description:
915. Uccle AC Zone Data Reduced to ACRS
ID:
ivo://CDS.VizieR/I/231
Title:
Uccle AC Zone Data Reduced to ACRS
Short Name:
I/231
Date:
21 Oct 2021
Publisher:
CDS
Description:
The U.S. Naval Observatory is in the process of making new reductions of the Astrographic Catalogue (AC) using a modern reference system, the ACRS, which represents the system of the FK5. The data from the Uccle Zone, whose plates are centered between declinations +34 and +35 degrees (eq. 1900), have been analyzed for scale, rotation, tilt, coma, magnitude equation, radial distortion and distortions introduced by the use of reseaux in the Carte du Ciel program. The result is a positional catalog of over 117,000 stars on eq. J2000.0, epoch of observation. Additionally, all stars have been matched with the Tycho Input Catalog (revised); those numbers have been added for additional identification purposes.
916. UCL DaCHS server TAP service
ID:
ivo://astro.ucl.ac.uk/tap
Title:
UCL DaCHS server TAP service
Short Name:
UCL Astro TAP
Date:
08 Mar 2017 14:59:34
Publisher:
astro.ucl.ac.uk
Description:
The UCL DaCHS server's TAP end point. The Table Access Protocol (TAP) lets you execute queries against our database tables, inspect various metadata, and upload your own data. It is thus the VO's premier way to access public data holdings. Tables exposed through this endpoint include: columns, groups, key_columns, keys, schemas, tables from the tap_schema schema, emptyobscore, obscore from the ivoa schema, epn_core from the mdisc schema.
917. UDS/COSMOS HiZELS galaxies
ID:
ivo://CDS.VizieR/J/MNRAS/428/1128
Title:
UDS/COSMOS HiZELS galaxies
Short Name:
J/MNRAS/428/1128
Date:
21 Oct 2021
Publisher:
CDS
Description:
This paper presents new deep and wide narrow-band surveys undertaken with United Kingdom Infrared Telescope (UKIRT), Subaru and the Very Large Telescope (VLT), a unique combined effort to select large, robust samples of H{alpha} star-forming galaxies at z = 0.40, 0.84, 1.47 and 2.23 (corresponding to look-back times of 4.2, 7.0, 9.2 and 10.6Gyr) in a uniform manner over ~2deg^2^ in the Cosmological Evolution Survey and Ultra Deep Survey fields. The deep multi-epoch H{alpha} surveys reach a matched 3{sigma} flux limit of ~3M_{sun}_/yr out to z=2.2 for the first time, while the wide area and the coverage over two independent fields allow us to greatly overcome cosmic variance and assemble by far the largest samples of H{alpha} emitters. Catalogues are presented for a total of 1742, 637, 515 and 807 H{alpha} emitters, robustly selected at z = 0.40, 0.84, 1.47 and 2.23, respectively, and used to determine the H{alpha} luminosity function and its evolution.
918. UGR photometry of LBG candidates at z~3
ID:
ivo://CDS.VizieR/J/A+A/563/A142
Title:
UGR photometry of LBG candidates at z~3
Short Name:
J/A+A/563/A142
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a deep multi wavelength imaging survey (UGR) in 3 different fields, Q0933, Q1623 and COSMOS, for a total area of ~1500arcmin^2^ The data were obtained with the Large Binocular Camera on the Large Binocular Telescope. To select our LBG candidates we adopt the well established and widely used color selection criterion (U-G vs. G-R). One of the main advantages of our survey is that it has a wider dynamic color range for U drop-out selection compared to previous studies. This allows us to fully exploit the depth of our R band images, obtaining a robust sample with few interlopers. In addition, for 2 of our fields we have spectroscopic redshift information that is necessary to better estimate the completeness of our sample and interloper fraction. Our limiting magnitudes reach 27.0(AB) in the R band (5{sigma}) and 28.6(AB) in the U band (1{sigma}). This dataset was used to derive Lyman Break Galaxy candidates at z~3. We obtained a catalog with a total of 12264 sources down to the 50% completeness magnitude limit in the R band for each field. We find a surface density of ~3 LBG candidates arcmin^-2^ down to R=25.5, where completeness is >=95% for all 3 fields. This number is higher than the original studies, but consistent with more recent samples.
919. UHECR
ID:
ivo://bsdc.icranet.org/uhecr/q/cone
Title:
UHECR
Short Name:
uhecr cone
Date:
18 Nov 2016 10:08:23
Publisher:
BSDC
Description:
An interactive catalog of Ultra High Energy Cosmic Rays
920. UKIDSS UDS field spectroscopic redshifts
ID:
ivo://CDS.VizieR/J/MNRAS/475/4148
Title:
UKIDSS UDS field spectroscopic redshifts
Short Name:
J/MNRAS/475/4148
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a large-scale galaxy structure Cl J021734-0513 at z~0.65 discovered in the UKIDSS UDS field, made of ~20 galaxy groups and clusters, spreading over 10Mpc. We report on a VLT/VIMOS spectroscopic follow-up program that, combined with past spectroscopy, allowed us to confirm four galaxy clusters (M_200_~10^14^M_{sun}_) and a dozen associated groups and star-forming galaxy overdensities. Two additional filamentary structures at z~0.62 and 0.69 and foreground and background clusters at 0.6<z<0.7 were also confirmed along the line of sight. The structure subcomponents are at different formation stages. The clusters have a core dominated by passive galaxies and an established red sequence. The remaining structures are a mix of star-forming galaxy overdensities and forming groups. The presence of quiescent galaxies in the core of the latter shows that 'pre-processing' has already happened before the groups fall into their more massive neighbours. Our spectroscopy allows us to derive spectral index measurements e.g. emission/absorption line equivalent widths, strength of the 4000{AA} break, valuable to investigate the star formation history of structure members. Based on these line measurements, we select a population of 'post-starburst' galaxies. These galaxies are preferentially found within the virial radius of clusters, supporting a scenario in which their recent quenching could be prompted by gas stripping by the dense intracluster medium. We derive stellar age estimates using Markov Chain Monte Carlo-based spectral fitting for quiescent galaxies and find a correlation between ages and colours/stellar masses which favours a top-down formation scenario of the red sequence. A catalogue of ~650 redshifts in UDS is released alongside the paper (via MNRAS online data).

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