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301. Galaxy morphology catalog
ID:
ivo://CDS.VizieR/J/AJ/134/1508
Title:
Galaxy morphology catalog
Short Name:
J/AJ/134/1508
Date:
21 Oct 2021
Publisher:
CDS
Description:
Careful inspection of large-scale photographs of Shapley-Ames galaxies seems to show a smooth transition between the morphological characteristics of galaxies located on the narrow red and on the broad blue sequences in the galaxian color-magnitude diagram. In other words, there does not appear to be a dichotomy between blue and red galaxies. Both the colors and the morphologies of galaxies are found to correlate strongly with their environments. Red and early-type Shapley-Ames galaxies are dominant in clusters, whereas blue late-type star-forming objects dominate the general field. Interestingly, the colors and morphologies of galaxies in small groups resemble the field and differ from those in clusters. As noted by Baade, the presence of dust and star formation are very closely correlated, except in a few galaxies that probably had unusual evolutionary histories. Over the entire range from S0 to Sc there is no significant difference between the integrated colors of normal and barred objects, suggesting that the formation of a bar does not significantly affect the stellar evolutionary history of a galaxy.
302. Galaxy morphology in the CFRS
ID:
ivo://CDS.VizieR/J/AJ/122/621
Title:
Galaxy morphology in the CFRS
Short Name:
J/AJ/122/621
Date:
21 Oct 2021
Publisher:
CDS
Description:
The images of 229 galaxies in the Canada-France Redshift Survey have been classified on the DDO system. These observations were combined with previous classifications of galaxies with known redshifts in the Hubble Deep Field. The combined sample provides homogeneous morphological classifications for 425 galaxies of known redshift. The fraction of all galaxies that are of type E, S0, or E/S0 appears to remain approximately constant at ~17% over the redshift range 0.25<z<1.2. Over the same range, the fraction of irregular (Ir) galaxies increases from ~5% to ~12%. Part of this increase may be due to mild luminosity evolution of Ir galaxies. The frequency of mergers is found to rise by a factor of 2 or 3 over the redshift range covered by the present survey. These results are in qualitative agreement with those obtained previously by Brinchmann et al. (Cat. <J/ApJ/499/112>) using a coarser galaxy classification system.
303. Galaxy pairs in the CNOC2 Redshift Survey
ID:
ivo://CDS.VizieR/J/ApJ/565/208
Title:
Galaxy pairs in the CNOC2 Redshift Survey
Short Name:
J/ApJ/565/208
Date:
21 Oct 2021
Publisher:
CDS
Description:
We investigate redshift evolution in the galaxy merger and accretion rates, using a well-defined sample of 4184 galaxies with 0.12<=z<=0.55 and R_C_<=21.5. We identify 88 galaxies in close (5<=rp<=20h^-1^kpc) dynamical ({Delta}<=500km/s) pairs. These galaxies are used to compute global pair statistics, after accounting for selection effects resulting from the flux limit, k-corrections, luminosity evolution, and spectroscopic incompleteness.
304. Galaxy properties at NGP
ID:
ivo://CDS.VizieR/VII/204
Title:
Galaxy properties at NGP
Short Name:
VII/204
Date:
21 Oct 2021
Publisher:
CDS
Description:
A two-color study of the galaxies detected on POSS-I in a 289deg^2^ region centered on the North Galactic Pole is presented. We use a variety of mapping techniques to characterize the large-scale spatial distribution of galaxies. The depth and sample size of this new survey allows, for the first time, the isolation of large photometric subsamples of galaxies in high- and low-density environments on the scale of superclusters. Our principal finding is a statistically significant difference between the mean photometric properties of these subsamples in the sense that galaxies in the high-density Coma and filament environments have redded colors and larger concentration indices than galaxies drawn from low-density interfilament regions. These results are in agreement with the known morphology-density relation.
305. Galaxy redshift catalogue
ID:
ivo://CDS.VizieR/J/MNRAS/236/207
Title:
Galaxy redshift catalogue
Short Name:
J/MNRAS/236/207
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present redshifts and blue magnitudes for a sample of 264 'field' galaxies virtually complete to a limiting magnitude of bj~=16.80mag. The galaxies were selected by sampling one galaxy in every three in order of apparent magnitude on each of nine high-latitude UK Schmidt (UKST) fields. Photometric data were provided by COSMOS machine measures of UKST plates, zero-pointed with CCD photometry. The spectral data came from observations with the 1.9-m telescope at the South African Astronomical Observatory (SAAO), and the resulting radial velocities have a precision of ~+/-130km/s. This survey augments substantially the Durham/AAT redshift survey. In this paper we discuss the observational techniques and reduction procedures.
306. Galaxy Redshifts
ID:
ivo://CDS.VizieR/VII/36
Title:
Galaxy Redshifts
Short Name:
VII/36
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Catalog of Galaxy Redshifts was compiled by Dr. Rood to enter the most accurate redshift for each entry in the Uppsala General Catalog of Galaxies below 15000 km/s, plus some fainter galaxies in the fields of rich clusters, plus some southern galaxies. The catalog is 99 percent complete for declinations north of -2.5deg and blue magnitude (Pmag) brighter than 13. The present documentation is mostly adapted from the "Documentation of the Machine-Readable Version of the Catalog of Galaxy Redshifts" by Theresa A. Nagy and Robert S. Hill, May 1981, prepared for NASA GSFC, Greenbelt, No SSD-T-5069-0013-81.
307. Galaxy stellar mass assembly
ID:
ivo://CDS.VizieR/VI/143
Title:
Galaxy stellar mass assembly
Short Name:
VI/143
Date:
21 Oct 2021
Publisher:
CDS
Description:
Semi-analytical models (SAMs) are currently the best way to understand the formation of galaxies within the cosmic dark-matter structures. They are able to give a statistical view of the variety of the evolutionary histories of galaxies in terms of star formation and stellar mass assembly. While they reproduce the local stellar mass functions, correlation functions and luminosity functions fairly well, they fail to match observations at high redshift (z>=3) in most cases, particularly in the low-mass range. The inconsistency between models and observations indicates that the history of gas accretion in galaxies, within their host dark-matter halo, and the transformation of gas into stars, are not followed well. We briefly present a new version of the GalICS semi-analytical model. With this new model, we explore the impact of classical mechanisms, such as supernova feedback or photoionization, on the evolution of the stellar mass assembly and the star formation rate. Even with strong efficiency, these two processes cannot explain the observed stellar mass function and star formation rate distribution or the stellar mass versus dark matter halo mass relation. We thus introduce an ad hoc modification of the standard paradigm, based on the presence of a no-star-forming gas component, and a concentration of the star-forming gas in galaxy discs. The main idea behind the existence of the no-star-forming gas reservoir is that only a fraction of the total gas mass in a galaxy is available to form stars. The reservoir generates a delay between the accretion of the gas and the star formation process. This new model is in much better agreement with the observations of the stellar mass function in the low-mass range than the previous models and agrees quite well with a large set of observations, including the redshift evolution of the specific star formation rate. However, it predicts a large amount of no-star-forming baryonic gas, potentially larger than observed, even if its nature has still to be examined in the context of the missing baryon problem.
308. Galaxy Zoo: A catalog of overlapping galaxy pairs
ID:
ivo://CDS.VizieR/J/PASP/125/2
Title:
Galaxy Zoo: A catalog of overlapping galaxy pairs
Short Name:
J/PASP/125/2
Date:
21 Oct 2021
Publisher:
CDS
Description:
Analysis of galaxies with overlapping images offers a direct way to probe the distribution of dust extinction and its effects on the background light. We present a catalog of 1990 such galaxy pairs selected from the Sloan Digital Sky Survey (SDSS) by volunteers of the Galaxy Zoo project. We highlight subsamples which are particularly useful for retrieving such properties of the dust distribution as UV extinction, the extent perpendicular to the disk plane, and extinction in the inner parts of disks. The sample spans wide ranges of morphology and surface brightness, opening up the possibility of using this technique to address systematic changes in dust extinction or distribution with galaxy type. This sample will form the basis for forthcoming work on the ranges of dust distributions in local disk galaxies, both for their astrophysical implications and as the low-redshift part of a study of the evolution of dust properties. Separate lists and figures show deep overlaps, where the inner regions of the foreground galaxy are backlit, and the relatively small number of previously-known overlapping pairs outside the SDSS DR7 sky coverage.
309. Gal. 2D phot. decompositions in r, g & i bands
ID:
ivo://CDS.VizieR/J/MNRAS/455/2440
Title:
Gal. 2D phot. decompositions in r, g & i bands
Short Name:
J/MNRAS/455/2440
Date:
21 Oct 2021
Publisher:
CDS
Description:
We extend the catalogue of two-dimensional, Point-Spread-Function-corrected de Vacouleurs, Sersic, de Vacouleurs+Exponential, and Sersic+Exponential fits of ~7x10^5^ galaxies presented in Meert+ (2015, J/MNRAS/446/3943) to include the g and i bands. Fits are analysed using the physically motivated flagging system presented in the original text, making adjustments for the differing signal to noise when necessary. We compare the fits in each of the g, r, and i bands. Fixed aperture magnitudes and colours are also provided for all galaxies.
310. GALEX Arecibo SDSS survey (GASS)
ID:
ivo://CDS.VizieR/J/MNRAS/403/683
Title:
GALEX Arecibo SDSS survey (GASS)
Short Name:
J/MNRAS/403/683
Date:
21 Oct 2021
Publisher:
CDS
Description:
We introduce the GALEX Arecibo SDSS Survey (GASS), an on-going large programme that is gathering high quality HI-line spectra using the Arecibo radio telescope for an unbiased sample of ~1000 galaxies with stellar masses greater than 10^10^M_{sun}_ and redshifts 0.025<z<0.05, selected from the Sloan Digital Sky Survey (SDSS) spectroscopic and Galaxy Evolution Explorer (GALEX) imaging surveys. The galaxies are observed until detected or until a low gas mass fraction limit (1.5-5 per cent) is reached. This paper presents the first Data Release, consisting of ~20 per cent of the final GASS sample. We use this data set to explore the main scaling relations of the HI gas fraction with galaxy structure and NUV-r colour.

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