- ID:
- ivo://CDS.VizieR/J/MNRAS/327/1004
- Title:
- Early-type galaxy parameters
- Short Name:
- J/MNRAS/327/1004
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We perform a series of comparisons between distance-independent photometric and spectroscopic properties used in the surface brightness fluctuation (SBF) and fundamental plane (FP) methods of early-type galaxy distance estimation. The data are taken from two recent surveys: the SBF Survey of Galaxy Distances and the Streaming Motions of Abell Clusters (SMAC) FP survey. We derive a relation between (V-I)0 colour and Mg2 index using nearly 200 galaxies and discuss implications for Galactic extinction estimates and early-type galaxy stellar populations.
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- ID:
- ivo://CDS.VizieR/J/A+AS/139/483
- Title:
- Early-type gal. kinematics in compact groups
- Short Name:
- J/A+AS/139/483
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present measurements of stellar kinematics for seven early-type galaxies in HCG 67, HCG 74, and HCG 79. These data are aimed at studying the relation between the environment and the dynamics, structure and stellar content of early-type galaxies. In the present three groups, the kinematic features we observed cannot be associated unambiguously to physical interactions. Visible morphological peculiarities do not appear correlated with kinematical perturbations.
- ID:
- ivo://CDS.VizieR/J/A+A/342/671
- Title:
- Early-type spiral galaxies kinematics
- Short Name:
- J/A+A/342/671
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the stellar and ionized-gas velocity curves and velocity-dispersion profiles along the major axis for six early-type spiral galaxies. Two of these galaxies, namely NGC 2179 and NGC 2775, are particularly suited for the study of dark matter halos. Using their luminosity profiles and modeling their stellar and gaseous kinematics, we derive the mass contributions of the luminous and the dark matter to the total potential. In NGC 2179 we find that the data (measured out to about the optical radius R_opt_) unambiguously require the presence of a massive dark halo. For the brighter and bigger object NGC 2775, we can rule out a significant halo contribution at radii R<~0.6R_opt_. Although preliminary, these results agree with the familiar mass distribution trend known for late-type spirals of comparable mass.
- ID:
- ivo://CDS.VizieR/J/MNRAS/321/277
- Title:
- EFAR Catalog. VII.
- Short Name:
- J/MNRAS/321/277
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present peculiar velocities for 85 clusters of galaxies in two large volumes at distances between 6000 and 15000km/s in the directions of Hercules-Corona Borealis and Perseus-Pisces-Cetus (the EFAR sample). These velocities are based on Fundamental Plane (FP) distance estimates for early-type galaxies in each cluster. We fit the FP using a maximum likelihood algorithm which accounts for both selection effects and measurement errors, and yields FP parameters with smaller bias and variance than other fitting procedures. We obtain a best-fitting FP with coefficients consistent with the best existing determinations. We measure the bulk motions of the sample volumes using the 50 clusters with the best-determined peculiar velocities.
- ID:
- ivo://CDS.VizieR/J/ApJS/106/1
- Title:
- EFAR cluster and galaxy selection
- Short Name:
- J/ApJS/106/1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The EFAR project is a study of 736 candidate elliptical galaxies in 84 clusters lying in two regions, toward Hercules-Corona Borealis and Perseus-Pisces-Cetus, at distances cz~6000-15000km/s. In this paper (the first of a series), we present an introduction to the EFAR project and describe in detail the selection of the clusters and galaxies in our sample. Fundamental data for the galaxies and clusters are given, including accurate new positions for each galaxy and redshifts for each cluster. The galaxy selection functions are determined by using diameters measured from Schmidt sky survey images for 2185 galaxies in the cluster fields. Future papers in this series will present the spectroscopic and photometric observations of this sample, investigate the properties of the fundamental plane for elliptical galaxies, and determine the large-scale peculiar velocity fields in these two regions of the universe.
- ID:
- ivo://CDS.VizieR/J/MNRAS/305/259
- Title:
- EFAR galaxies redshifts & velocity dispersions
- Short Name:
- J/MNRAS/305/259
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the spectroscopic data for the galaxies studied in the EFAR project, which is designed to measure the properties and peculiar motions of early-type galaxies in two distant regions. We have obtained 1319 spectra of 714 early-type galaxies over 33 observing runs on 10 different telescopes. We describe the observations and data reductions used to measure redshifts, velocity dispersions and the Mgb and Mg_2_ Lick linestrength indices. Detailed simulations and intercomparison of the large number of repeat observations lead to reliable error estimates for all quantities. The measurements from different observing runs are calibrated to a common zero-point or scale before being combined, yielding a total of 706 redshifts, 676 velocity dispersions, 676 Mgb linestrengths and 582 Mg_2_ linestrengths. The median estimated errors in the combined measurements are {Delta}cz=20km/s, {Delta}sigma/sigma=9.1%, {Delta}Mgb/Mgb=7.2% and {Delta}Mg_2_=0.015mag. Comparison of our measurements with published data sets shows no systematic errors in the redshifts or velocity dispersions, and only small zero-point corrections to bring our linestrengths on to the standard Lick system. We have assigned galaxies to physical clusters by examining the line-of-sight velocity distributions based on EFAR and ZCAT redshifts, together with the projected distributions on the sky. We derive mean redshifts and velocity dispersions for these clusters, which will be used in estimating distances and peculiar velocities and to test for trends in the galaxy population with cluster mass. The spectroscopic parameters presented here for 706 galaxies combine high-quality data, uniform reduction and measurement procedures, and detailed error analysis. They form the largest single set of velocity dispersions and linestrengths for early-type galaxies published to date.
- ID:
- ivo://CDS.VizieR/J/MNRAS/292/499
- Title:
- EFAR photometric data
- Short Name:
- J/MNRAS/292/499
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present R-band CCD photometry for 776 galaxies observed in the EFAR (Elliptical FAR away) project. The photometry is compared with photoelectric data, showing that a common zero-point good to better than 1% and a precision of 0.03mag per zero-point have been achieved. We give the circularly averaged surface brightness profiles and the photometric parameters of the 762 program galaxies, D(n) diameters (at 20.5mag/arcsec^2^), half-luminosity radii Re, total magnitudes m_T_, and average effective surface brightnesses <SBe>. More than 80% of the profiles have a global S/N ratio larger than 300. The extrapolation needed to derive total magnitudes is less than 10% for 80% of the fits. More than 80% of the galaxies have mean effective surface brightness larger than the observed sky brightness. In 90% of the profiles the estimate of the contamination of the sky by the galaxy light is less than 1%. We derive total magnitudes and half-luminosity radii to better than 0.15mag and 25%, respectively, for 90% of our sample. In contrast, external comparisons show that data in the literature can be strongly affected by systematic errors due to large extrapolations, small radial range, sky subtraction errors, seeing effects, and the use of a simple R^1/4^ fit. The resulting errors can easily amount to more than 0.5mag in the total magnitudes and 50% in the half-luminosity radii.
- ID:
- ivo://CDS.VizieR/J/ApJS/201/31
- Title:
- Emission-line galaxies from SDSS. I.
- Short Name:
- J/ApJS/201/31
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Recently, much attention has been paid to double-peaked narrow emission-line (NEL) galaxies, some of which are suggested to be related to merging galaxies. We make a systematic search to build the largest sample of these sources from Data Release 7 of the Sloan Digital Sky Survey (SDSS). With reasonable criteria for fluxes, FWHMs of the emission lines, and separations of the peaks, we select 3030 double-peaked NEL galaxies. In light of the existence of broad Balmer lines and the locations of the two components of double-peaked NELs distinguished by the Kauffmann et al. (2003MNRAS.346.1055K) criteria in the Baldwin-Phillips-Terlevich diagram, we find that there are 81 Type I active galactic nuclei (AGNs), 837 double Type II AGNs (2-Type II), 708 galaxies with double star-forming components (2-SF), 400 with mixed star-forming and Type II AGN components (Type II + SF), and 1004 unknown-type objects. As a by-product, a sample of galaxies (12582) with asymmetric or top-flat profiles of emission lines is established. After visually inspecting the SDSS images of the two samples, we find 54 galaxies with dual cores.
- ID:
- ivo://CDS.VizieR/J/A+A/342/1
- Title:
- ESO Slice Project. VI. Groups of Galaxies.
- Short Name:
- J/A+A/342/1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In Table 1 we present our group catalog. For each group we list the ID number (column 1), the number of members (column 2), the coordinates {alpha}_(1950)_ and {delta}_(1950)_ (columns 3 and 4 respectively), the mean radial velocity cz in km/s corrected for Virgo infall and galactic rotation (column 5), and the velocity dispersion {sigma}_cz_ (column 6). We compute the velocity dispersion following the prescription of Ledermann (1984) for an unbiased estimator of the dispersion (see previous section). We also take into account the cosmological expansion of the universe and the measurement errors according to the prescriptions of Danese et al. (1980A&A....82..322D). The errors we associate to the redshifts are those output by the RVSAO cross-correlation procedure multiplied by a factor 1.6. This factor brings the cross-correlation error in rough agreement with the external error estimated from repeated observations (Vettolani et al., 1998, Cat. <J/A+AS/130/323> -- here we do not distinguish between emission and absorption line redshifts).
- ID:
- ivo://CDS.VizieR/J/A+A/524/A6
- Title:
- Evolution of spectral early-type galaxies
- Short Name:
- J/A+A/524/A6
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We study the evolution of spectral early-type galaxies in clusters, groups, and the field up to redshift 0.9 using the ESO Distant Cluster Survey (EDisCS) dataset. We measure structural parameters (circularized half-luminosity radii Re, surface brightness Ie, and velocity dispersions sigma) for 154 cluster and 68 field galaxies. On average, we achieve precisions of 10% in Re, 0.1dex in logIe, and 10% in sigma. We sample ~20% of cluster and ~10% of field spectral early-type galaxies to an I band magnitude in a 1arcsec radius aperture as faint as I1=22. We study the evolution of the zero point of the fundamental plane (FP) and confirm results in the literature, but now also for the low cluster velocity dispersion regime.
