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631. OCA Data Center TAP service
ID:
ivo://purx/dachs/tap
Title:
OCA Data Center TAP service
Short Name:
OCA DC TAP
Date:
04 Mar 2022 16:03:46
Publisher:
Observatoire de la Côte d'Azur
Description:
The OCA Data Center'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: epn_core from the mp3c_best_epn schema, best, body, mpcorb, name, prop_albedo, prop_diameter, prop_family, prop_g, prop_h, prop_mass, prop_proper_elements, version from the mp3c_main schema, columns, groups, key_columns, keys, schemas, tables from the tap_schema schema.
632. [OII] luminosity function
ID:
ivo://CDS.VizieR/J/A+A/575/A40
Title:
[OII] luminosity function
Short Name:
J/A+A/575/A40
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the [OII] luminosity function measured in the redshift range 0.1<z<1.65 with unprecedented depth and accuracy. Our measurements are based on medium resolution flux-calibrated spectra of emission line galaxies with the FORS2 instrument at VLT and with the SDSS-III/BOSS spectrograph. The FORS2 spectra and the corresponding catalog containing redshifts and line fluxes are released along with this paper. In this work we use a novel method to combine the aforementioned surveys with GAMA, zCOSMOS and VVDS, which have different target selection, producing a consistent weighting scheme to derive the [OII] luminosity function. The measured luminosity function is in good agreement with previous independent estimates. The comparison with two state-of-the-art semi-analytical models is good, which is encouraging for the production of mock catalogs of [OII] flux limited surveys. We observe the bright end evolution over 8.5Gyr: we measure the decrease of logL* from 42.4erg/s at redshift 1.44 to 41.2 at redshift 0.165 and we find that the faint end slope flattens when redshift decreases. This measurement confirms the feasibility of the target selection of future baryonic acoustic oscillation surveys aiming at observing [OII] flux limited samples.
633. [OII] nebular emission from MgII absorbers
ID:
ivo://CDS.VizieR/J/MNRAS/471/1910
Title:
[OII] nebular emission from MgII absorbers
Short Name:
J/MNRAS/471/1910
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present nebular emission associated with 198 strong Mg II absorbers at 0.35<=z<=1.1 in the fibre spectra of quasars from the Sloan Digital Sky Survey. Measured [OII] luminosities (L_[OII]_) are typical of sub-L* galaxies with derived star formation rate (uncorrected for fibre losses and dust reddening) in the range of 0.5-20M_{sun}_/yr. Typically less than ~3 per cent of the MgII systems with rest equivalent width, W_2796_>=2{AA}, show L_[OII]_>=0.3L*_[OII]_. The detection rate is found to increase with increasing W_2796_ and z. No significant correlation is found between W_2796_ and L_[OII]_ even when we restrict the samples to narrow z ranges. A strong correlation is seen between L_[OII]_ and z. While this is expected from the luminosity evolution of galaxies, we show that finite fibre size plays a very crucial role in this correlation. The measured nebular line ratios (like [OIII]/[OII] and [OIII]/H {beta}) and their z evolution are consistent with those of galaxies detected in deep surveys. Based on the median stacked spectra, we infer the average metallicity (logZ~8.3), ionization parameter (logq~7.5) and stellar mass (log (M/M_{sun}_)~9.3). The MgII systems with nebular emission typically have W_2796_>=2{AA}, MgII doublet ratio close to 1 and W(FeII{lambda}2600)/W_2796_~0.5 as often seen in damped Ly {alpha} and 21-cm absorbers at these redshifts. This is the biggest reported sample of [OII] emission from MgII absorbers at low-impact parameters ideally suited for probing various feedback processes at play in z<=1 galaxies.
634. On the nature of small galaxy systems
ID:
ivo://CDS.VizieR/J/MNRAS/481/2458
Title:
On the nature of small galaxy systems
Short Name:
J/MNRAS/481/2458
Date:
21 Oct 2021
Publisher:
CDS
Description:
We aim at defining homogeneous selection criteria of small galaxy systems in order to build catalogues suitable to compare main properties of pairs, triplets, and groups with four or more members. To this end we use spectroscopic and photometric Sloan Digital Sky Survey (SDSS) data to identify systems with a low number of members. We study global properties of these systems and the properties of their member galaxies finding that galaxies in groups are systematically redder and with lower star formation activity indicators than galaxies in pairs which have a higher fraction of star-forming galaxies. Triplet galaxies present intermediate trends between pairs and groups. We also find an enhancement of star formation activity for galaxies in small systems with companions closer than 100kpc, irrespective of the number of members. We have tested these analyses on SDSS mock catalogues derived from the Millennium simulation, finding as conservative thresholds 76 per cent completeness and a contamination of 23 per cent in small galaxy systems, when considering an extreme case of incompleteness due to fiber collisions. Nevertheless, we also found that the results obtained are not likely affected by projection effects. Our studies suggest that an extra galaxy in a system modify the properties of the member galaxies. In pairs, galaxy-galaxy interactions increase gas density and trigger starbursts. However, repeated interactions in triplets and groups can generate gas stripping, turbulence, and shocks quenching the star formation in these systems.
635. Optical properties of Markarian galaxies
ID:
ivo://CDS.VizieR/J/ApJS/170/33
Title:
Optical properties of Markarian galaxies
Short Name:
J/ApJS/170/33
Date:
21 Oct 2021
Publisher:
CDS
Description:
A database for the entire Markarian catalog is presented that combines extensive new measurements of their optical parameters with a literature and database search. The measurements were made using images extracted from the STScI Digitized Sky Survey (DSS) of F_pg_(red) and J_pg_(blue) band photographic sky survey plates obtained by the Palomar and UK Schmidt telescopes. We provide accurate coordinates, morphological type, spectral and activity classes, red and blue apparent magnitudes, apparent diameters, axial ratios, and position angles, as well as number counts of neighboring objects in a circle of radius 50kpc. Special attention was paid to the individual descriptions of the galaxies in the original Markarian lists, which clarified many cases of misidentifications of the objects, particularly among interacting systems, larger galaxies with knots of star formation, possible stars, and cases of stars projected on galaxies. The total number of individual Markarian objects in the database is now 1544.
636. Optical spectral atlas of Seyfert nuclei
ID:
ivo://CDS.VizieR/J/ApJS/98/477
Title:
Optical spectral atlas of Seyfert nuclei
Short Name:
J/ApJS/98/477
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present an optical spectral atlas of the nuclear region (generally 2"x4", or r=<200pc) of a magnitude-limited survey of 486 nearby galaxies having B_T_=<12.5mag and {delta}>0deg. The double spectrograph on the Hale 5m telescope yielded simultaneous spectral coverage of ~4230-5110A and ~6210-6860A, with a spectral resolution of ~4A in the blue half and ~2.5A in the red half. This large, statistically significant survey contains uniformly observed and calibrated moderate-dispersion spectra of exceptionally high quality. The data presented in this paper will be used for various systematic studies of the physical properties of the nuclei of nearby galaxies, with special emphasis on searching for low-luminosity active galactic nuclei, or "dwarf" Seyferts. Our survey led to the discovery of four relatively obvious but previously uncataloged Seyfert galaxies (NGC 3735, 4395, 4639, and 6951), and many more galactic nuclei showing subtle evidence for Seyfert activity. We have also identified numerous low-ionization nuclear emission-line regions (LINERs), some of which may be powered by nonstellar processes. Of the many "starburst" nuclei in our sample, several exhibit the spectral features of Wolf-Rayet stars.
637. OSA VST ATLAS Survey
ID:
ivo://wfau.roe.ac.uk/osa-tap
Title:
OSA VST ATLAS Survey
Short Name:
WFAU OSA TAP
Date:
28 May 2018 17:35:25
Publisher:
WFAU, Institute for Astronomy, University of Edinburgh
Description:
This service hosts the public releases of the ATLAS Survey housed at the Wide Field Astronomy Unit at the Univeristy of Edinburgh, as well as a number of other external datasets for which WFAU has neighbour tables, that can be cross matched with ATLAS. The initial aim of ATLAS is to survey 4500 deg2 of the Southern Sky at high galactic latitudes to comparable depths to the SDSS in the North. The VST ATLAS will be the first step towards a panoramic digital survey of the Southern Sky in the optical bands. The ATLAS will complement the proposed VISTA Hemisphere Survey in the South.
638. OSUG Virtual Observatory TAP service
ID:
ivo://osug-vo.osug/tap
Title:
OSUG Virtual Observatory TAP service
Short Name:
OSUG TAP
Date:
09 Jan 2020 07:54:53
Publisher:
OSUG Virtual Observatory
Description:
The OSUG Virtual Observatory'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: epn_core from the sshade_spectra schema, obscore from the ivoa schema, columns, groups, key_columns, keys, schemas, tables from the tap_schema schema.
639. outlier detection algorithm for SDSS galaxies
ID:
ivo://CDS.VizieR/J/MNRAS/465/4530
Title:
outlier detection algorithm for SDSS galaxies
Short Name:
J/MNRAS/465/4530
Date:
21 Oct 2021
Publisher:
CDS
Description:
How can we discover objects we did not know existed within the large data sets that now abound in astronomy? We present an outlier detection algorithm that we developed, based on an unsupervised Random Forest. We test the algorithm on more than two million galaxy spectra from the Sloan Digital Sky Survey and examine the 400 galaxies with the highest outlier score. We find objects which have extreme emission line ratios and abnormally strong absorption lines, objects with unusual continua, including extremely reddened galaxies. We find galaxy-galaxy gravitational lenses, double-peaked emission line galaxies and close galaxy pairs. We find galaxies with high ionization lines, galaxies that host supernovae and galaxies with unusual gas kinematics. Only a fraction of the outliers we find were reported by previous studies that used specific and tailored algorithms to find a single class of unusual objects. Our algorithm is general and detects all of these classes, and many more, regardless of what makes them peculiar. It can be executed on imaging, time series and other spectroscopic data, operates well with thousands of features, is not sensitive to missing values and is easily parallelizable.
640. Oxford 2 AC Zone Data Reduced to ACRS
ID:
ivo://CDS.VizieR/I/225
Title:
Oxford 2 AC Zone Data Reduced to ACRS
Short Name:
I/225
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 Oxford 2 Zone, whose plates are centered between declinations +32 and +33 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.

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