- ID:
- ivo://CDS.VizieR/J/A+A/580/A18
- Title:
- Carina Project VIII. {alpha}-element abundances
- Short Name:
- J/A+A/580/A18
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have performed a new abundance analysis of Carina red giant (RG) stars from spectroscopic data collected with UVES (high spectral resolution) and FLAMES/GIRAFFE (high and medium resolution) at ESO/VLT. The former sample includes 44 RGs, while the latter consists of 65 (high-resolution) and ~800 (medium-resolution) RGs, covering a significant fraction of the galaxy's RG branch, and red clump stars. To improve the abundance analysis at the faint magnitude limit, the FLAMES/GIRAFFE data were divided into ten surface gravity and effective temperature bins. The spectra of the stars belonging to the same gravity and temperature bin were stacked. This approach allowed us to increase the signal-to-noise ratio in the faint magnitude limit (V>=20.5mag) by at least a factor of five. We took advantage of the new photometry index c_U,B,I_ introduced recently as an age and probably a metallicity indicator to split stars along the red giant branch. These two stellar populations display distinct [Fe/H] and [Mg/H] distributions: their mean iron abundances are -2.15+/-0.06dex ({sigma}=0.28), and -1.75+/-0.03dex ({sigma}=0.21), respectively. The two iron distributions differ at the 75% level. This supports preliminary results. Moreover, we found that the old and intermediate-age stellar populations have mean [Mg/H] abundances of -1.91+/-0.05dex ({sigma}=0.22) and -1.35+/-0.03dex ({sigma}=0.22); these differ at the 83% level. Carina's - element abundances agree, within 1{sigma}, with similar abundances for field halo stars and for cluster (Galactic and Magellanic) stars. The same outcome applies to nearby dwarf spheroidals and ultra-faint dwarf galaxies in the iron range covered by Carina stars. Finally, we found evidence of a clear correlation between Na and O abundances, thus suggesting that Carina's chemical enrichment history is quite different from that in the globular clusters.
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- ID:
- ivo://CDS.VizieR/J/ApJ/862/100
- Title:
- Carnegie-Irvine Galaxy Survey VII. S0 galaxies
- Short Name:
- J/ApJ/862/100
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using high-quality optical images from the Carnegie-Irvine Galaxy Survey, we perform multicomponent decompositions of S0 galaxies (S0s) to derive accurate structural parameters to constrain their physical origin. Many S0s do not host prominent bulges. S0s have a broad distribution of bulge-to-total ratios (B/T) and Sersic indices (n), with average values of B/T=0.34+/-0.15 and n=2.62+/-1.02, qualitatively consistent with the notion that S0s define a parallel sequence with and may have evolved from spiral galaxies. This is further reinforced by the incidence of bars and lenses in S0s, which, when compared with the statistics in spirals, supports the idea that lenses are demised bars. However, despite their wide range of prominence, the bulges of S0s form a surprisingly uniform sequence on both the Kormendy and fundamental plane relations. There is no evidence for population dichotomy or other indications of differentiation into classical and pseudo bulges. Most of the S0s reside in the field and in groups; cluster environment is not a necessary condition for S0 production. The properties of S0 bulges show little correlation with environmental indicators, after the dependence of galaxy stellar mass on environment is taken into account. As the bulges of late-type spirals and S0s are intrinsically different, and environmental effects that may account for such evolution appear to be minimal, we conclude that late- type spirals are not plausible progenitors of S0s. The bulges of S0s likely formed at an early epoch, after which secular processes contributed little to their subsequent evolution.
- ID:
- ivo://CDS.VizieR/J/AJ/109/2376
- Title:
- Case blue/emission-line galaxies
- Short Name:
- J/AJ/109/2376
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present CCD imaging and spectroscopic data for 176 blue and/or emission-line galaxies from Lists I and II of the Case Northern Sky Survey. Our sample consists of all Case galaxies which lie in the region which overlaps the original Slice of the Universe survey. We use the observational data to investigate the physical properties of the galaxies selected by the surveys to compare with various parameters published in the survey lists, and to investigate the selection characteristics and completeness limit of the survey. The majority of the Case galaxies are energized by regions of active star formation; only 5% of the sample are Seyfert galaxies. The dual selection techniques used (both UV-excess and emission lines) allow the survey to detect star-forming galaxies with a wide range of properties and evolutionary states. In particular, the Case survey selects galaxies with lower levels of activity than most previous surveys. The survey also includes a larger fraction of intermediate and low-luminosity galaxies than would be present in a purely magnitude-limited sample. Although galaxies as faint as m_B_=19 are present in the sample, the completeness limit of the UV-excess selected portion of the survey is closer to m_B_=16. The luminosity function of the Case galaxies is derived and compared with that of the "normal" field galaxies in the same volume of space. The shape of the Case luminosity function is similar to that for the field sample. A surprising result is that 31% of the field galaxy population can be accounted for by galaxies of the type selected in the Case survey.
- ID:
- ivo://CDS.VizieR/J/ApJ/659/162
- Title:
- CAS parameters of 199 nearby galaxies
- Short Name:
- J/ApJ/659/162
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a quantitative analysis of the morphologies for 199 nearby galaxies as parameterized with measurements of the concentration, asymmetry, and clumpiness (CAS) parameters at wavelengths from 0.15 to 0.85um. We find that these CAS parameters depend on both galaxy type and the wavelength of observation. As such, we use them to obtain a quantitative measure of the "morphological k-correction", i.e., the change in appearance of a galaxy with rest-frame wavelength.
- ID:
- ivo://CDS.VizieR/J/ApJ/640/603
- Title:
- Catalog of AGNs in the GOODS fields
- Short Name:
- J/ApJ/640/603
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present mid-infrared observations of active galactic nuclei (AGNs) in the GOODS fields, performed with the Spitzer Space Telescope. These are the deepest infrared and X-ray fields to date and cover a total area of 0.1{deg}^2^. AGNs are selected on the basis of their hard (28keV) X-ray emission.
- ID:
- ivo://CDS.VizieR/J/MNRAS/411/373
- Title:
- Catalog of AKARI Deep Field South
- Short Name:
- J/MNRAS/411/373
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The AKARI Deep Field-South (ADF-S) is a ~12deg^2^ region near the South Ecliptic Pole that has been observed with deep scans in the far-infrared by the AKARI satellite. As such it is becoming one of the key extragalactic survey fields. We here present complementary observations of the ADF-S conducted by the Spitzer Space Telescope at wavelengths of 24 and 70um. We extract source catalogues at each of these wavelengths reaching depths of ~0.2mJy at 24um and ~20mJy at 70um. We also apply a K-to-24um colour criterion to select objects with galaxy-like colours in the 24-um survey. Completeness corrections as a function of flux density are derived for both catalogues by injecting artificial sources of known flux density into the maps, and we find that our surveys are 50 per cent complete at 0.26 and 24mJy at 24 and 70um, respectively.
- ID:
- ivo://CDS.VizieR/J/other/Ap/41.1
- Title:
- Catalog of barred galaxies
- Short Name:
- J/other/Ap/41.1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A catalog of barred spiral galaxies of types SB and SAB with B_T_=<13.5 and DE>-10{deg} has been compiled. Some parameters of these galaxies are given.
- ID:
- ivo://CDS.VizieR/J/ApJS/224/40
- Title:
- Catalog of Chandra ACIS point like sources
- Short Name:
- J/ApJS/224/40
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Chandra archival data is a valuable resource for various studies on different X-ray astronomy topics. In this paper, we utilize this wealth of information and present a uniformly processed data set, which can be used to address a wide range of scientific questions. The data analysis procedures are applied to 10029 Advanced CCD Imaging Spectrometer observations, which produces 363530 source detections belonging to 217828 distinct X-ray sources. This number is twice the size of the Chandra Source Catalog (Version 1.1). The catalogs in this paper provide abundant estimates of the detected X-ray source properties, including source positions, counts, colors, fluxes, luminosities, variability statistics, etc. Cross-correlation of these objects with galaxies shows that 17828 sources are located within the D_25_ isophotes of 1110 galaxies, and 7504 sources are located between the D_25_ and 2D_25_ isophotes of 910 galaxies. Contamination analysis with the log N-log S relation indicates that 51.3% of objects within 2D_25_ isophotes are truly relevant to galaxies, and the "net" source fraction increases to 58.9%, 67.3%, and 69.1% for sources with luminosities above 10^37^, 10^38^, and 10^39^erg/s, respectively. Among the possible scientific uses of this catalog, we discuss the possibility of studying intra-observation variability, inter-observation variability, and supersoft sources (SSSs). About 17092 detected sources above 10 counts are classified as variable in individual observation with the Kolmogorov-Smirnov (K-S) criterion (P_K-S_<0.01). There are 99647 sources observed more than once and 11843 sources observed 10 times or more, offering us a wealth of data with which to explore the long-term variability. There are 1638 individual objects (~2350 detections) classified as SSSs. As a quite interesting subclass, detailed studies on X-ray spectra and optical spectroscopic follow-up are needed to categorize these SSSs and pinpoint their properties. In addition, this survey can enable a wide range of statistical studies, such as X-ray activity in different types of stars, X-ray luminosity functions in different types of galaxies, and multi-wavelength identification and classification of different X-ray populations.
- ID:
- ivo://CDS.VizieR/J/ApJS/97/77
- Title:
- Catalog of Coma Cluster Galaxies
- Short Name:
- J/ApJS/97/77
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A homogeneous photometry catalog is presented for 450 galaxies with B25.5 <= 16 mag located in the 9.8 x 9.8 deg region centred on the Coma Cluster. The catalog is based on photographic photometry using an automated surface photometry software for data reduction applied to B-band Schmidt plates. The catalog provides accurate positions, isophotal and total magnitudes, major and minor axes, and a few other photometric parameters including rudimentary morphology (early or late type).
- ID:
- ivo://CDS.VizieR/J/ApJ/744/82
- Title:
- Catalog of cosmic voids from the SDSS-DR7
- Short Name:
- J/ApJ/744/82
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using a large sample of galaxies from the the seventh data release of the Sloan Digital Sky Survey (SDSS-DR7), we have analyzed the alignment of disk galaxies around cosmic voids. We have constructed a complete sample of cosmic voids (devoid of galaxies brighter than M_r_-5log h=-20.17) with radii larger than 10h^-1^Mpc up to redshift 0.12. Disk galaxies in shells around these voids have been used to look for particular alignments between the angular momentum of the galaxies and the radial direction of the voids. We find that disk galaxies around voids larger than >~15h^-1^Mpc within distances not much larger than 5h^-1^Mpc from the surface of the voids present a significant tendency to have their angular momenta aligned with the void's radial direction with a significance >~98.8% against the null hypothesis. The strength of this alignment is dependent on the void's radius and for voids with a radius >~15h^-1^Mpc the distribution of the orientation of the galaxies is compatible with a random distribution. Finally, we find that this trend observed in the alignment of galaxies is similar to the one observed for the minor axis of dark matter halos around cosmic voids found in cosmological simulations, suggesting a possible link in the evolution of both components.
