- 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.
Number of results to display per page
Search Results
- ID:
- ivo://CDS.VizieR/J/A+A/506/1071
- Title:
- Galaxy morphology in 5 medium redshift clusters
- Short Name:
- J/A+A/506/1071
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Following the study presented in our previous paper, based on the Nordic Optical Telescope (NOT) sample, which consists of five clusters of galaxies within the redshift range 0.18<=z<=0.25 imaged in the central 0.5-2Mpc in very good seeing conditions, we have studied the quantitative morphology of their bright galaxy population. We analyzed the surface brightness profiles of the galaxy population in those clusters, after performing simulations in order to check the reliability of the fits. We also derived a quantitative morphological classification.
- 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.
- ID:
- ivo://CDS.VizieR/J/MNRAS/388/1537
- Title:
- Galaxy pairs from SDSS-DR2
- Short Name:
- J/MNRAS/388/1537
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We investigate the incidence of major mergers creating massive (M_star_>10^11^M_{sun}_) galaxies in present-day (z<=0.12) groups and clusters. Using a volume-limited sample of 845 groups with dark matter halo masses above 2.5x10^13^M_{sun}_, we isolate 221 galaxy pairs with <=1.5 r-band magnitude differences, <=30kpc projected separations and combined masses above 10^11^M_{sun}_. We fit the r-band images of each pair as the line-of-sight projection of symmetric models and identify 38 mergers by the presence of residual asymmetric structure associated with both progenitors, such as non-concentric isophotes, broad and diffuse tidal tails and dynamical friction wakes.
- 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.
1236. 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.
- 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.
1238. 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.
- ID:
- ivo://CDS.VizieR/J/MNRAS/243/390
- Title:
- Galaxy redshift survey in a Coma strip
- Short Name:
- J/MNRAS/243/390
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- (no description available)
1240. Galaxy rotation curves
- ID:
- ivo://CDS.VizieR/J/ApJ/636/721
- Title:
- Galaxy rotation curves
- Short Name:
- J/ApJ/636/721
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We apply the modified acceleration law obtained from Einstein gravity coupled to a massive skew-symmetric field F_{mu}{nu}{lambda}_ to the problem of explaining galaxy rotation curves without exotic dark matter. Our sample of galaxies includes low surface brightness (LSB) and high surface brightness (HSB) galaxies and an elliptical galaxy. In those cases for which photometric data are available, a best fit via the single parameter (M/L)_stars_ to the luminosity of the gaseous (HI plus He) and luminous stellar disks is obtained. In addition, a best fit to the rotation curves of galaxies is obtained in terms of a parametric mass distribution (independent of luminosity observations) - a two-parameter fit to the total galactic mass (or mass-to-light ratio M/L) and a core radius associated with a model of the galaxy cores - using a nonlinear least-squares fitting routine including estimated errors. The fits are compared to those obtained using Milgrom's phenomenological MOND model and to the predictions of the Newtonian/Kepler acceleration law.
