- ID:
- ivo://CDS.VizieR/J/A+AS/142/353
- Title:
- CDD V photometry of B2 radio galaxies
- Short Name:
- J/A+AS/142/353
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The results of V-band CCD photometry for 72 low-luminosity radio galaxies from the B2 sample is presented. Most of these galaxies are of early type and their photometric and morphological properties are studied in the paper. We present the resulting surface brightness profiles and isophote parameters' profiles, including ellipticity, position angle, and B4, for 59 galaxies.
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- ID:
- ivo://CDS.VizieR/J/ApJS/170/95
- Title:
- Centaurus Cluster catalog
- Short Name:
- J/ApJS/170/95
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalog of all galaxies with V<=22.0 and R_iso_>3" within a 0.83deg^2^ region centered on the Centaurus Cluster (Abell 3526) at RA=12h48m, DE=-41{deg}18'. V-band total magnitudes along with other photometric parameters were obtained from the detection programs FOCAS and SExtractor and also from fitting curve-of-growth Sersic functions to the galaxy profiles. Central surface brightnesses, half-light radii, ellipticity, and position angles are presented, along with (B-V) aperture colors where B-band data were obtained. This work is part of a larger program to study the cluster-to-cluster variation in the faint end of the LF based on the study of eight clusters, including Centaurus. We discuss our data reduction methods in this paper. More detailed analyses and science results will be presented in subsequent papers.
- ID:
- ivo://CDS.VizieR/J/AJ/129/2138
- Title:
- Centers of early-type galaxies with HST
- Short Name:
- J/AJ/129/2138
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present observations of 77 early-type galaxies imaged with the PC1 CCD of the Hubble Space Telescope (HST) WFPC2. "Nuker-law" parametric fits to the surface brightness profiles are used to classify the central structure into "core" or "power-law" forms.
- ID:
- ivo://CDS.VizieR/J/MNRAS/398/1129
- Title:
- Central galaxies in groups and clusters
- Short Name:
- J/MNRAS/398/1129
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using a statistically representative sample of 911 central galaxies (CENs) from the Sloan Digital Sky Survey (SDSS) Data Release 4 group catalogue, we study how the structure (shape and size) of the first rank (by stellar mass) group and cluster members depends on (1) galaxy stellar mass (M_star_), (2) the global environment defined by the dark matter halo mass (M_halo_) of the host group and (3) the local environment defined by their special halocentric position. We quantify the structure of SDSS galaxies with a galfit-based pipeline that fits two-dimensional Sersic models to the r-band image data. Through tests with simulated and real galaxy images, we demonstrate that our pipeline can recover Sersic parameters without significant bias. Moreover, to test the impact of local environment on CENs, we compare the structure of CENs with that satellite galaxies (SATs) of comparable M_star_.
- ID:
- ivo://CDS.VizieR/J/ApJ/722/L120
- Title:
- Central surface brightness of 30000 SDSS galaxies
- Short Name:
- J/ApJ/722/L120
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Disc central surface brightness for 30000 galaxies from the Sloan Digitized Sky Survey (SDSS) Data Release 7, in the r-band. Virtual Observatory methods and tools were used to define, retrieve and analyze the images for this unprecedentedly large sample classified as spiral galaxies in the LEDA catalogue. These parameters are also available for all other SDSS bands (u,g,i,z), and they can be retrieved from the Author.
- ID:
- ivo://CDS.VizieR/J/ApJ/827/L19
- Title:
- Central surface densities in SPARC disk galaxies
- Short Name:
- J/ApJ/827/L19
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We use the Spitzer Photometry and Accurate Rotation Curves (SPARC) database to study the relation between the central surface density of stars {Sigma}_*_(0) and dynamical mass {Sigma}_dyn_(0) in 135 disk galaxies (S0 to dIrr). We find that {Sigma}_dyn_(0) correlates tightly with {Sigma}_*_(0) over 4dex. This central density relation can be described by a double power law. High surface brightness galaxies are consistent with a 1:1 relation, suggesting that they are self-gravitating and baryon dominated in the inner parts. Low surface brightness (LSB) galaxies systematically deviate from the 1:1 line, indicating that the dark matter contribution progressively increases but remains tightly coupled to the stellar one. The observed scatter is small (~0.2dex) and largely driven by observational uncertainties. The residuals show no correlations with other galaxy properties like stellar mass, size, or gas fraction.
- ID:
- ivo://CDS.VizieR/J/ApJ/464/79
- Title:
- CFRS XI: High-redshift field galaxies morphology
- Short Name:
- J/ApJ/464/79
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The 143 galaxies with secure redshifts (Z_median_=0.62) from the 1415+52 field of the Canada-France Redshift Survey have been imaged with median seeing of 0.67" (FWHM). Structural parameters have been derived by fitting multicomponent models and the results confirm two phenomena seen in a smaller sample of galaxies imaged with the Hubble Space Telescope. First, 11+/-3% of the galaxies lie off the normal locus of color versus bulge fraction B/T. This class of objects ("blue nucleated galaxies," or BNGs) was identified using HST observations (Schade et al. 1995ApJ...451L...1S, hereafter CFRS IX), and it was shown that they are associated with peculiar/asymmetric structure and merger/interactions. The observed frequency of BNGs in this sample is 14+/-4% 0.5<z<1.2 and 6^+6^_-3_% at 0.2<z<0.5, but the true frequency is likely to be a factor ~2 higher after corrections are made for the effect of asymmetric/peculiar structures. Galaxy disks at 0.5<z<1.1 are found to have a mean rest-frame, inclination-corrected central surface brightness of {mu}_AB_(B)=19.8+/-0.1mag/arcsec^2^, ~1.6mag brighter than the Freeman (1970ApJ...160..811F) value. At low redshift (0.2<z<0.5) the mean surface brightness [{mu}_AB_(B)=21.3+/-0.25] is consistent with the Freeman value. These results are consistent with the HST observations. With larger numbers of galaxies and therefore more statistical weight they demonstrate the capabilities, and limits, of ground-based work in the study of galaxy morphology at high redshift.
- ID:
- ivo://CDS.VizieR/J/ApJ/845/87
- Title:
- CGS. V. Statistical study of bars and buckled bars
- Short Name:
- J/ApJ/845/87
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Simulations have shown that bars are subject to a vertical buckling instability that transforms thin bars into boxy or peanut-shaped structures, but the physical conditions necessary for buckling to occur are not fully understood. We use the large sample of local disk galaxies in the Carnegie-Irvine Galaxy Survey to examine the incidence of bars and buckled bars across the Hubble sequence. Depending on the disk inclination angle (i), a buckled bar reveals itself as either a boxy/peanut-shaped bulge (at high i) or as a barlens structure (at low i). We visually identify bars, boxy/peanut-shaped bulges, and barlenses, and examine the dependence of bar and buckled bar fractions on host galaxy properties, including Hubble type, stellar mass, color, and gas mass fraction. We find that the barred and unbarred disks show similar distributions in these physical parameters. The bar fraction is higher (70%-80%) in late-type disks with low stellar mass (M*<10^10.5^M_{sun}_) and high gas mass ratio. In contrast, the buckled bar fraction increases to 80% toward massive and early-type disks (M*>10^10.5^M_{sun}_), and decreases with higher gas mass ratio. These results suggest that bars are more difficult to grow in massive disks that are dynamically hotter than low-mass disks. However, once a bar forms, it can easily buckle in the massive disks, where a deeper potential can sustain the vertical resonant orbits. We also find a probable buckling bar candidate (ESO506-G004) that could provide further clues to understand the timescale of the buckling process.
- ID:
- ivo://CDS.VizieR/J/MNRAS/454/952
- Title:
- Chandra Deep Field-South ATLAS 5.5GHz DR2
- Short Name:
- J/MNRAS/454/952
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a new image of the 5.5GHz radio emission from the extended Chandra Deep Field South. Deep radio observations at 5.5GHz were obtained in 2010 and presented in the first data release. A further 76h of integration has since been obtained, nearly doubling the integration time. This paper presents a new analysis of all the data. The new image reaches 8.6{mu}Jy rms, an improvement of about 40% in sensitivity. We present a new catalogue of 5.5GHz sources, identifying 212 source components, roughly 50% more than were detected in the first data release. Source counts derived from this sample are consistent with those reported in the literature for S_5.5GHz_>0.1mJy but significantly lower than published values in the lowest flux density bins (S_5.5GHz_<0.1mJy), where we have more detected sources and improved statistical reliability. The 5.5GHz radio sources were matched to 1.4GHz sources in the literature and we find a mean spectral index of -0.35+/-0.10 for S_5.5GHz_>0.5mJy, consistent with the flattening of the spectral index observed in 5GHz sub-mJy samples. The median spectral index of the whole sample is {alpha}_med_=-0.58, indicating that these observations may be starting to probe the star-forming population. However, even at the faintest levels (0.05<S_5.5GHz_<0.1mJy), 39% of the 5.5GHz sources have flat or inverted radio spectra. Four flux density measurements from our data, across the full 4.5-6.5GHz bandwidth, are combined with those from literature and we find 10% of sources (S_5.5GHz_>~0.1mJy) show significant curvature in their radio spectral energy distribution spanning 1.4-9GHz.
- ID:
- ivo://CDS.VizieR/J/AZh/91/679
- Title:
- Chandra X-Ray galaxy clusters at z <1.4
- Short Name:
- J/AZh/91/679
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A reconstruction of the total mass (the fraction of dark matter, intercluster gas, and the brightest galaxy of the cluster) of 128 X-ray galaxy clusters at redshifts 0.01-1.4 based on Chandra observations is presented. The total mass M200 and the baryonic mass Mb have been measured for all the sample objects, as well as the concentration parameter c200, which characterizes the size of the dark matter halo. The existence of a tight correlation between c200 and M200 is confirmed, c{prop.to}M^a^_vir_/(1+z)b with a=-0.56+/-0.15 and b=0.80+/-0.25 (95% confidence level), in good agreement with the predictions of numerical simulations and previous observations. Fitting the inner dark-matter density slope {alpha} with a generalized NFW model yields {alpha}=1.10+/-0.48 at the 2{sigma} confidence level, combining the results for the entire sample, for which the model gives a good description of the data. There is also a tight correlation between the inner slope of the dark-matter density profile {alpha} and the baryonic mass contentMb for massive galaxy clusters, namely, {alpha} decreases with increasing baryonic mass content. A simple power-law model is used to fit the {alpha}-M_b_ distributions, yielding the break point for the inner slope of the dark-matter density profile b=1.72+/-0.37 (68% confidence level).
