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- ID:
- ivo://CDS.VizieR/VII/139
- Title:
- Observations of Galaxies 1985-1989
- Short Name:
- VII/139
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this catalog a complete list of new publications which include CO observations of external galaxies has been edited so that new observations are reported only once, preferably in refereed journals (pub.dat). Therefore the catalog of publications also serves as an inventory of distinct observational projects. This catalog lists all publications that have appeared since the submission of Verter (1985) and before the end of 1989. For each publication, the number and nature of the observations are summarized.
- ID:
- ivo://CDS.VizieR/J/A+A/535/A38
- Title:
- Observations of NOAO Bootes field at 153MHz
- Short Name:
- J/A+A/535/A38
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present deep, high-resolution radio interferometric observations at 153MHz to complement the extensively studied NOAO Bootes field. We provide a description of the observations, data reduction and source catalog construction. From our single pointing GMRT observation of ~12 hours we obtain a high-resolution (26"x22") image of ~11.3 square degrees, fully covering the Bootes field region and beyond.
- ID:
- ivo://CDS.VizieR/J/ApJ/788/72
- Title:
- Observed sample of z~0.7 massive galaxies
- Short Name:
- J/ApJ/788/72
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Detailed studies of the stellar populations of intermediate-redshift galaxies can shed light onto the processes responsible for the growth of the massive galaxy population in the last 8 billion years. We here take a step toward this goal by means of deep, multiobject rest-frame optical spectroscopy, performed with the Inamori Magellan Areal Camera and Spectrograph on the Magellan telescope, of a sample of ~70 galaxies in the Extended Chandra Deep Field South survey with redshift 0.65<=z<=0.75, apparent R>22.7 mag_Vega_, and stellar mass >10^10^ M_{sun}_. We measure velocity dispersion and stellar absorption features for individual sources. We interpret them by means of a large Monte Carlo library of star formation histories, following the Bayesian approach adopted for previous low redshift studies, and derive constraints on the stellar mass, mean stellar age, and stellar metallicity of these galaxies. We characterize for the first time the relations between stellar age and stellar mass and between stellar metallicity and stellar mass at z~0.7 for the galaxy population as a whole and for quiescent and star-forming galaxies separately. These relations of increasing age and metallicity with galaxy mass for the galaxy population as a whole have a similar shape as the z~0.1 analog derived for Sloan Digital Sky Survey galaxies but are shifted by -0.28 dex in age and by -0.13 dex in metallicity, at odds with simple passive evolution. Considering z=0.7 quiescent galaxies alone, we find that no additional star formation and chemical enrichment are required for them to evolve into the present-day quiescent population. However, other observations require the quiescent population to grow from z=0.7 to the present day. This growth could be supplied by the quenching of a fraction of z=0.7 M_{sstarf}_>10^11^ M_{sun}_ star-forming galaxies with metallicities already comparable to those of quiescent galaxies, thus leading to the observed increase of the scatter in age without affecting the metallicity distribution. However, rapid quenching of the entire population of massive star-forming galaxies at z=0.7 would be inconsistent with the age- and metallicity-mass relations for the population as a whole and with the metallicity distribution of star-forming galaxies only, which are, on average, 0.12 dex less metal rich than their local counterparts. This indicates chemical enrichment until the present in at least a fraction of the z=0.7 star-forming galaxies in our sample.
- ID:
- ivo://CDS.VizieR/J/AJ/134/2385
- Title:
- Occulting galaxy pairs in SDSS
- Short Name:
- J/AJ/134/2385
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A spiral galaxy partially overlapping a more distant elliptical offers a unique opportunity to measure the dust extinction in the foreground spiral. From the Sloan Digital Sky Survey (SDSS) DR4 spectroscopic sample, we selected 83 occulting galaxy pairs and measured disk opacity over the redshift range z=0.0-0.2 with the goal of determining the recent evolution of disk dust opacity. The enrichment of the ISM changes over the lifetime of a disk, and it is reasonable to expect the dust extinction properties of spiral disks as a whole to change over their lifetime. When they do, the change will affect our measurements of galaxies over the observable universe. From the SDSS pairs we conclude that spiral disks show evidence of extinction to ~2 effective radii.
2686. OCSVM anomalies
- ID:
- ivo://CDS.VizieR/J/A+A/606/A39
- Title:
- OCSVM anomalies
- Short Name:
- J/A+A/606/A39
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Wide-angle photometric surveys of previously uncharted sky areas or wavelength regimes will always bring in unexpected sources - novelties or even anomalies - whose existence and properties cannot be easily predicted from earlier observations. Such objects can be efficiently located with novelty detection algorithms. Here we present an application of such a method, called one-class support vector machines (OCSVM), to search for anomalous patterns among sources preselected from the mid-infrared AllWISE catalogue covering the whole sky. To create a model of expected data we train the algorithm on a set of objects with spectroscopic identifications from the SDSS DR13 database, present also in AllWISE. The OCSVM method detects as anomalous those sources whose patterns - WISE photometric measurements in this case - are inconsistent with the model. Among the detected anomalies we find artefacts, such as objects with spurious photometry due to blending, but more importantly also real sources of genuine astrophysical interest. Among the latter, OCSVM has identified a sample of heavily reddened AGN/quasar candidates distributed uniformly over the sky and in a large part absent from other WISE-based AGN catalogues. It also allowed us to find a specific group of sources of mixed types, mostly stars and compact galaxies. By combining the semi-supervised OCSVM algorithm with standard classification methods it will be possible to improve the latter by accounting for sources which are not present in the training sample, but are otherwise well-represented in the target set. Anomaly detection adds flexibility to automated source separation procedures and helps verify the reliability and representativeness of the training samples. It should be thus considered as an essential step in supervised classification schemes to ensure completeness and purity of produced catalogues.
- ID:
- ivo://CDS.VizieR/J/MNRAS/469/3363
- Title:
- Offset discs and bars in SDSS galaxies
- Short Name:
- J/MNRAS/469/3363
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We use multiwavelength Sloan Digital Sky Survey (SDSS) images and Galaxy Zoo morphologies to identify a sample of ~270 late-type galaxies with an off-centre bar. We measure offsets in the range 0.2-2.5kpc between the photometric centres of the stellar disc and stellar bar. The measured offsets correlate with global asymmetries of the galaxies, with those with largest offsets showing higher lopsidedness. These findings are in good agreement with predictions from simulations of dwarf-dwarf tidal interactions producing off-centre bars. We find that the majority of galaxies with off-centre bars are of Magellanic type, with a median mass of 10^9.6^M_{sun}_, and 91 per cent of them having M*<3x10^10^M_{sun}_, the characteristic mass at which galaxies start having higher central concentrations attributed to the presence of bulges. We conduct a search for companions to test the hypothesis of tidal interactions, but find that a similar fraction of galaxies with offset bars have companions within 100kpc as galaxies with centred bars. Although this may be due to the incompleteness of the SDSS spectroscopic survey at the faint end, alternative scenarios that give rise to offset bars such as interactions with dark companions or the effect of lopsided halo potentials should be considered. Future observations are needed to confirm possible low-mass companion candidates and to determine the shape of the dark matter halo, in order to find the explanation for the off-centre bars in these galaxies.
- ID:
- ivo://CDS.VizieR/J/AcA/51/221
- Title:
- OGLE-II. Cepheids in IC 1613
- Short Name:
- J/AcA/51/221
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present results of the search for Cepheids in the galaxy IC 1613 carried out as a sub-project of the OGLE-II microlensing survey. 138 Cepheids were found in the 14.2'x14.2' region in the center of the galaxy. We present light curves, VI photometry and basic data for all these objects, as well as color-magnitude diagram of the observed field.
- ID:
- ivo://CDS.VizieR/J/AJ/133/496
- Title:
- OH megamasers infrared photometry
- Short Name:
- J/AJ/133/496
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- OH megamasers are the most luminous masers in the universe. The total of 109 OH megamaser (OHM) galaxies known so far have been collected, and cross-identifications of those OHM galaxies with Two Micron All Sky Survey (2MASS) sources are made in this paper. Using 2MASS (Cat. II/246) and IRAS (Cat. II/125, II/156) data, the infrared properties of OHM-detected and non-detected sources are compared.
- ID:
- ivo://CDS.VizieR/J/ApJS/172/456
- Title:
- [OII] emitting galaxies in COSMOS & SDF fields
- Short Name:
- J/ApJS/172/456
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have carried out a wide-field imaging survey for [OII] {lambda}3727 emitting galaxies at z~1.2 in the HST COSMOS 2 square degree field using the Suprime-Cam on the Subaru Telescope. The survey covers a sky area of 6700arcmin^2^ in the COSMOS field, and a redshift range between 1.17 and 1.20 ({Delta}z=0.03), corresponding to a survey volume of 5.56x10^5^Mpc^3^. We obtain a sample of 3176 [OII] emitting galaxies with observed emission-line equivalent widths greater than 26{AA}. Since our survey tends to sample brighter [OII] emitting galaxies, we also analyze a sample of fainter [OII] emitting galaxies found in the Subaru Deep Field (SDF). We find an extinction-corrected [OII] luminosity density of 10Exp(40.35^+0.08^_-0.06_)^erg/s/Mpc^3^, corresponding to star formation rate density of 0.32^+0.06^_-0.04_ M_{sun}_/yr/Mpc^3^ in the COSMOS field at z~1.2. This is the largest survey for [OII] emitters beyond z=1 currently available.
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