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921. Ultra compact dwarf galaxies catalog
ID:
ivo://CDS.VizieR/J/A+A/625/A50
Title:
Ultra compact dwarf galaxies catalog
Short Name:
J/A+A/625/A50
Date:
21 Oct 2021
Publisher:
CDS
Description:
Photometric surveys of galaxy clusters have revealed a large number of ultra compact dwarfs (UCDs) around predominantly massive elliptical galaxies. Their origin is still debated as some UCDs are considered to be the remnant nuclei of stripped dwarf galaxies while others seem to mark the high-mass end of the star cluster population. We aim to characterize the properties of a UCD found at very close projected distance (r_wproj_=1.1kpc) from the centre of the low-mass (M~10^10^M_{sun}_) early-type galaxy FCC 47. This is a serendipitous discovery from MUSE adaptive optics science verification data. We explore the potential origin of this UCD as either a massive cluster or the remnant nucleus of a dissolved galaxy. We used archival Hubble Space Telescope data to study the photometric and structural properties of FCC 47-UCD1. In the MUSE data, the UCD is unresolved, but we used its spectrum to determine the radial velocity and metallicity. The surface brightness of FCC 47-UCD1 is best described by a single King profile with low concentration C=Rt/Rc~10 and large effective radius (r_eff_=24pc). Its integrated magnitude and blue colour (Mg=-10.55mag, (g-z)=1.46mag) combined with a metallicity of [M/H]=-1.12+/-0.10dex and an age >8Gyr obtained from the full fitting of the MUSE spectrum suggests a stellar population mass of M*=4.87x10^6^M_{sun}_. The low S/N of the MUSE spectrum prevents detailed stellar population analysis. Due to the limited spectral resolution of MUSE, we can only give an upper limit on the velocity dispersion ({sigma}<17km/s), and consequently on its dynamical mass (M_dyn_<1.3x10^7^M_{sun}_). The origin of the UCD cannot be constrained with certainty. The low metallicity, old age, and magnitude are consistent with a star cluster origin, whereas the extended size is consistent with an origin as the stripped nucleus of a dwarf galaxy with a initial stellar mass of a few 10^8^M_{sun}_.
922. Ultracool Dwarf Companion Catalogue UCDC
ID:
ivo://org.gavo.dc/ucdc/q/cone
Title:
Ultracool Dwarf Companion Catalogue UCDC
Short Name:
UCDC cone
Date:
27 Dec 2024 08:31:03
Publisher:
The GAVO DC team
Description:
The Ultracool Dwarf Companion Catalogue consists of 278 multiple systems, 32 of which are newly discovered, each with at least one spectroscopically confirmed Ultracool Dwarf, within a 100 pc volume-limited sample. This catalogue is compiled using the Gaia Catalogue of Nearby Stars for stellar primaries and the Gaia Ultracool Dwarf Sample for low-mass companions and includes 241 doubles, 33 triples, and 4 higher-order systems established from positional, proper motion, and parallax constraints.
923. Ultra-deep catalog of X-ray groups in ECDF-S
ID:
ivo://CDS.VizieR/J/A+A/576/A130
Title:
Ultra-deep catalog of X-ray groups in ECDF-S
Short Name:
J/A+A/576/A130
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the detection, identification and calibration of extended sources in the deepest X-ray dataset to date, the Extended Chandra Deep Field South (ECDF-S). Ultra-deep observations of ECDF-S with Chandra and XMM-Newton enable a search for extended X-ray emission down to an unprecedented flux of 2x10^-16^ergs/s/cm^2^. By using simulations and comparing them with the Chandra and XMM data, we show that it is feasible to probe extended sources of this flux level, which is 10000 times fainter than the first X-ray group catalogs of the ROSAT all sky survey. Extensive spectroscopic surveys at the VLT and Magellan have been completed, providing spectroscopic identification of galaxy groups to high redshifts. Furthermore, available HST imaging enables a weak-lensing calibration of the group masses. We present the search for the extended emission on spatial scales of 32" in both Chandra and XMM data, covering 0.3 square degrees and model the extended emission on scales of arcminutes. We present a catalog of 46 spectroscopically identified groups, reaching a redshift of 1.6. We show that the statistical properties of ECDF-S, such as logN-logS and X-ray luminosity function are broadly consistent with LCDM, with the exception that dn/dz/d{Omega} test reveals that a redshift range of 0.2<z<0.5 in ECDF-S is sparsely populated. The lack of nearby structure, however, makes studies of high-redshift groups particularly easier both in X-rays and lensing, due to a lower level of clustered foreground. We present one and two point statistics of the galaxy groups as well as weak-lensing analysis to show that the detected low-luminosity systems are indeed low-mass systems. We verify the applicability of the scaling relations between the X-ray luminosity and the total mass of the group, derived for the COSMOS survey to lower masses and higher redshifts probed by ECDF-S by means of stacked weak lensing and clustering analysis, constraining any possible departures to be within 30% in mass. Ultra-deep X-ray surveys uniquely probe the low-mass galaxy groups across a broad range of redshifts. These groups constitute the most common environment for galaxy evolution. Together with the exquisite data set available in the best studied part of the Universe, the ECDF-S group catalog presented here has an exceptional legacy value.
924. Ultra-deep near-IR observation in HDF-S
ID:
ivo://CDS.VizieR/J/AJ/125/1107
Title:
Ultra-deep near-IR observation in HDF-S
Short Name:
J/AJ/125/1107
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present deep near-infrared (NIR) Js-, H-, and Ks-band ISAAC imaging of the Wide Field Planetary Camera 2 (WFPC2) field of the Hubble Deep Field South (HDF-S). The 2.5'x2.5' high Galactic latitude field was observed with the Very Large Telescope under the best seeing conditions, with integration times amounting to 33.6hr in Js, 32.3hr in H, and 35.6hr in Ks. We reach total AB magnitudes for point sources of 26.8, 26.2, and 26.2, respectively (3sigma), which make it the deepest ground-based NIR observation to date and the deepest Ks-band data in any field. The effective seeing of the co-added images is ~0.45" in Js, ~0.48" in H, and ~0.46" in Ks. Using published WFPC2 optical data, we constructed a Ks-limited multicolor catalog containing 833 sources down to K^tot^_s,AB_<~26, of which 624 have seven-band optical-to-NIR photometry. These data allow us to select normal galaxies from their rest-frame optical properties to high redshift (z<~4). The observations, data reduction, and properties of the final images are discussed, and we address the detection and photometry procedures that were used in making the catalog. In addition, we present deep number counts, color distributions, and photometric redshifts of the HDF-S galaxies.
925. Ultraviolet Excess Galaxies
ID:
ivo://CDS.VizieR/VII/63
Title:
Ultraviolet Excess Galaxies
Short Name:
VII/63
Date:
21 Oct 2021
Publisher:
CDS
Description:
The catalog contains a list of 412 faint galaxies selected for their apparent ultraviolet excess. The galaxies were selected from a 3-color (UBV) plate taken with the Palomar 48-inch Schmidt telescope. The 14-inch-square plates cover an area of 30 square degrees centered on Kapteyn Selected Area 28. The catalog includes running numbers, coordinates, color codes, magnitude codes, morphologies, diameters, and notes. The catalogued galaxies were selected by eye from the Palomar Schmidt 3-color (UBV) plate PS24771, centered on Kapteyn Selexted Area 28 and taken by Usher under conditions of good seeing and transparency.
926. ULYSSES supplement to GRB 3B catalog
ID:
ivo://CDS.VizieR/J/ApJS/120/399
Title:
ULYSSES supplement to GRB 3B catalog
Short Name:
J/ApJS/120/399
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present interplanetary network localization information for 218 gamma-ray bursts in the third BATSE catalog obtained by analyzing the arrival times of these bursts with the Ulysses and Compton Gamma Ray Observatory spacecraft. For any given burst observed by these two spacecraft, arrival time analysis (or "triangulation") results in an annulus of possible arrival directions whose half-width varies between 7'' and 32', depending on the intensity and time history of the burst and the distance of the Ulysses spacecraft from Earth. This annulus generally intersects the BATSE error circle, which results in an average reduction of a factor of 30 of the error box area.
927. 15um AKARI observations in CDFS field
ID:
ivo://CDS.VizieR/J/PASJ/61/177
Title:
15um AKARI observations in CDFS field
Short Name:
J/PASJ/61/177
Date:
21 Oct 2021
Publisher:
CDS
Description:
Deep observations of the Chandra Deep Field South have been secured at 15um with AKARI/IRC infrared space telescope. From these observations, we define a sample of mid infrared-selected galaxies at 15um and we also obtain 15um flux densities for a sample of Lyman Break Galaxies at z~1 already observed at 24um with Spitzer/MIPS.
928. 3.6um S4G Galactic bars characterization
ID:
ivo://CDS.VizieR/J/A+A/587/A160
Title:
3.6um S4G Galactic bars characterization
Short Name:
J/A+A/587/A160
Date:
21 Oct 2021
Publisher:
CDS
Description:
Stellar bars play an essential role in the secular evolution of disk galaxies because they are responsible for the redistribution of matter and angular momentum. Dynamical models predict that bars become stronger and longer in time, while their rotation speed slows down. We use the Spitzer Survey of Stellar Structure in Galaxies (S^4^G) 3.6um imaging to study the properties (length and strength) and fraction of bars at z=0 over a wide range of galaxy masses (M*~=10^8^-10^11^M_{sun}_) and Hubble types (-3<=T<=10). We calculated gravitational forces from the 3.6um images for galaxies with a disk inclination lower than 65{deg}. We used the maximum of the tangential-to-radial force ratio in the bar region (Qb) as a measure of the bar-induced perturbation strength for a sample of ~600 barred galaxies. We also used the maximum of the normalized m=2 Fourier density amplitude (A_2_^max^) and the bar isophotal ellipticity ({epsilon}) to characterize the bar. Bar sizes were estimated i) visually, ii) from ellipse fitting, iii) from the radii of the strongest torque, and iv) from the radii of the largest m=2 Fourier amplitude in the bar region. By combining our force calculations with the HI kinematics from the literature, we estimated the ratio of the halo-to-stellar mass (Mh/M*) within the optical disk and by further using the universal rotation curve models, we obtained a first-order model of the rotation curve decomposition of 1128 disk galaxies. We probe possible sources of uncertainty in our Qb measurements: the assumed scale height and its radial variation, the influence of the spiral arms torques, the effect of non-stellar emission in the bar region, and the dilution of the bar forces by the dark matter halo (our models imply that only ~10% of the disks in our sample are maximal). We find that for early- and intermediate-type disks (-3<=T<5), the relatively modest influence of the dark matter halo leads to a systematic reduction of the mean Qb by about 10-15%, which is of the same order as the uncertainty associated with estimating the vertical scale height. The halo correction on Qb becomes important for later types, implying a reduction of ~20-25% for T=7-10. Whether the halo correction is included or not, the mean Qb shows an increasing trend with T. However, the mean A_2_^max^ decreases for lower mass late-type systems. These opposing trends are most likely related to the reduced force dilution by bulges when moving towards later type galaxies. Nevertheless, when treated separately, both the early- and late-type disk galaxies show a strong positive correlation between Qb and A_2_^max^. For spirals the mean {epsilon}~0.5 is nearly independent of T, but it drops among S0s (~0.2). The Qb and {epsilon} show a relatively tight dependence, with only a slight difference between early and late disks. For spirals, all our bar strength indicators correlate with the bar length (scaled to isophotal size). Late-type bars are longer than previously found in the literature. The bar fraction shows a double-humped distribution in the Hubble sequence (~75% for Sab galaxies), with a local minimum at T=4 (~40%), and it drops for M*<~10^9.5-10^M_{sun}_. If we use bar identification methods based on Fourier decomposition or ellipse fitting instead of the morphological classification, the bar fraction decreases by ~30-50% for late-type systems with T>=5 and correlates with Mh/M*. Our Mh/M* ratios agree well with studies based on weak lensing analysis, abundance matching, and halo occupation distribution methods, under the assumption that the halo inside the optical disk contributes roughly a constant fraction of the total halo mass (~4%). We find possible evidence for the growth of bars within a Hubble time, as (1) bars in early-type galaxies show larger density amplitudes and disk-relative sizes than their intermediate-type counterparts, and (2) long bars are typically strong. We also observe two clearly distinct types of bars, between early- and intermediate-type galaxies (T<5) on one side, and the late-type systems on the other, based on the differences in the bar properties. Most likely this distinction is connected to the higher halo-to-stellar ratio that we observe in later types, which affects the disk stability properties.
929. UNAM-KIAS catalog of isolated galaxies
ID:
ivo://CDS.VizieR/J/AJ/139/2525
Title:
UNAM-KIAS catalog of isolated galaxies
Short Name:
J/AJ/139/2525
Date:
21 Oct 2021
Publisher:
CDS
Description:
A new catalog of isolated galaxies from the Sloan Digital Sky Survey Data Release 5 (SDSS DR5) is presented. A total of 1520 isolated galaxies were found in 1.4sr of sky. The selection criteria in this UNAM-KIAS catalog are a variation on the criteria developed by Karachentseva, including full redshift information. Through an image processing pipeline that takes advantage of the high-resolution (~0.4"/pix) and high dynamic range of the SDSS images, a uniform g-band morphological classification for all these galaxies is presented.
930. Unbiased sample of CSS and GPS
ID:
ivo://CDS.VizieR/J/MNRAS/416/1135
Title:
Unbiased sample of CSS and GPS
Short Name:
J/MNRAS/416/1135
Date:
21 Oct 2021
Publisher:
CDS
Description:
Compact Steep Spectrum (CSS) and Gigahertz Peaked Spectrum (GPS) sources are classes of compact, powerful, extragalactic objects. These sources are thought to be the earliest stages in the evolution of radio galaxies, capturing the ignition (or, in some cases, re-ignition) of the active galactic nucleus. As well as serving as probes of the early stages of large-scale radio sources, these sources are good, stable, amplitude calibrators for radio telescopes. We present an unbiased flux density limited (>1.5Jy at 2.7GHz) catalogue of these objects in the Southern hemisphere, including tabulated data, radio spectra, and where available, optical images and measurements. The catalogue contains 26 sources, consisting of two new candidates and 15 known CSS sources, and nine known GPS sources. We present new Australia Telescope Compact Array (ATCA) data on 10 of these 26 sources, and data on a further 42 sources which were excluded from our final sample. This bright sample will serve as a reference sample for comparison with subsequent faint (mJy level) samples of CSS and GPS candidates currently being compiled.

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