- ID:
- ivo://CDS.VizieR/J/MNRAS/274/1071
- Title:
- Edinburgh-Milano cluster redshift survey
- Short Name:
- J/MNRAS/274/1071
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this paper, we present the redshifts of the galaxies and galaxy clusters which form the Edinburgh-Milano (EM) cluster redshift survey. A total of 777 galaxy redshifts have been measured in 94 clusters extracted from the digitized Edinburgh-Durham Cluster Catalogue. We also present the radial velocity dispersions for 37 clusters. Observational and data reduction techniques are discussed in detail, together with the strategy adopted to determine the mean redshift of a cluster and to identify and discard plausible phantom clusters. Some 10 per cent of our clusters show heavy contamination, indicating that projection is a serious problem for optically selected, rich clusters. The median velocity dispersion estimated for a subsample of richness R>=1 clusters is 742+/-63km/s. From a simple comparison with {OMEGA}=1 cold dark matter models of structure formation, these results favour a biasing parameter b=1.6-2.0 and are inconsistent with a bias outside of the range b=1.3-2.5.
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Search Results
- ID:
- ivo://CDS.VizieR/J/A+A/578/A105
- Title:
- EELGs out to z~1 in zCOSMOS
- Short Name:
- J/A+A/578/A105
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present line measurements and physical properties of a sample of 165 extreme emission-line galaxies (EELGs) in the zCOSMOS 20k-Bright Survey (Lilly et al., 2009, Cat. J/ApJS/184/218). The zCOSMOS spectra consist of ~1h integrations in the medium resolution LRRED grism setting (R~600 with 2.5{AA}/pixel), covering a wavelength range 5550<{lambda}<9650{AA}. Measured emission-line fluxes are given in units of 10^-17^erg/s/cm^2^. Flux errors have been derived following Perez-Montero et al. (2013A&A...549A..25P) and Amorin et al. (2012ApJ...749..185A and 2012ApJ...754L..22A). No extinction correction has been applied to these fluxes. For each galaxy the reddening constant, c(H{beta}), is presented. These values and their corresponding uncertainties have been derived from the H{alpha}/H{beta} or H{gamma}/H{beta} ratios, whenever possible. A reddening constant derived from the SED best-fitting was adopted for (a) those galaxies where the computation of c(H{beta}) from emission lines is not possible because of the lack of lines, or (b) the corresponding line ratio produces a negative extinction correction (i.e., Ha/Hb<2.82 or Hg/Hb<0.47, assuming Case B recombination with T_e_=2*10^4K, n_e_=100cm^-3^). Stellar mass and 1{sigma} uncertainties have been obtained from SED fitting (Bolzonella et al., 2010A&A...524A..76B) after removal of the flux contribution from strong emission lines.
4063. EEMSS new X-ray clusters
- ID:
- ivo://CDS.VizieR/J/ApJ/566/744
- Title:
- EEMSS new X-ray clusters
- Short Name:
- J/ApJ/566/744
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The complete ensemble of Einstein Imaging Proportional Counter (IPC) X-ray images has been reprocessed and reanalyzed using a multiaperture source detection algorithm. A catalog of 772 new source candidates detected within the 38' diameter central regions of the 1435 IPC fields comprising the Extended Medium-Sensitivity Survey (EMSS) has been compiled. By comparison, 478 EMSS sources fall within the same area of sky. A randomly selected subsample of 133 fields was examined; 73 sources were detected and compared with 49 original EMSS sources in the same region of sky.
4064. EFAR Catalog. VII.
- 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.
4066. EFAR photometric data
- 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/A+A/411/559
- Title:
- Effective temperature for 181 F-K dwarfs
- Short Name:
- J/A+A/411/559
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Line depth ratios measured on high resolution (R=42000), high S/N echelle spectra are used for the determination of precise effective temperatures of 181 F, G, K main Sequence stars with about solar metallicity (-0.5<[Fe/H]<+0.5). A set of 105 relations is obtained which rely Teff on ratios of the strengths of lines with high and low excitation potentials, calibrated against previously published precise (1%) temperature estimates. The application range of the calibrations is 4000-6150K (F8V-K7V). The internal error of a single calibration is less than 100K, while the combination of all calibrations for a spectrum of S/N=100 reduces uncertainty to only 5-10K, and for S/N=200 or higher to better than 5K. The zero point of the temperature scale is directly defined from reflection spectra of the Sun with an uncertainty about 1K. The application of this method to investigation of the planet host stars properties is discussed.
- ID:
- ivo://CDS.VizieR/J/A+A/444/941
- Title:
- Effective temperature of B stars
- Short Name:
- J/A+A/444/941
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We establish an empirical effective temperature calibration of main sequence, luminosity class V to III B-type stars for the Delta a photometric system which was originally developed to detect magnetic chemically peculiar objects of the upper main sequence (early B-type to early F-type) at 5200A. However, this system provides the index g1-y which shows an excellent correlation with B-V as well as b-y and can be used as an indicator of the effective temperature. This is supplemented by a very accurate color-magnitude diagram, y or V versus g1-y, which can be used, for example, to determine the reddening, distance and age of an open cluster. This makes the Delta a photometric system an excellent tool to investigate the HR diagram in more detail. Using the reddening-free parameters and already established calibrations within the Stromgren uvbybeta, Geneva 7-color and Johnson UBV systems, a polynomial fit of third degree for the averaged effective temperatures to the individual (g1-y)0 values was derived. For this purpose, data from the literature as well as new observations were taken resulting in 225 suitable bright normal B-type objects. The statistical mean of the error for this sample is 238K which is sufficient to investigate the HRD of distant galactic open clusters as well as extragalactic aggregates in the future.
- ID:
- ivo://CDS.VizieR/J/A+A/443/851
- Title:
- Effective temperature of 30 Dor population
- Short Name:
- J/A+A/443/851
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The star-formation history and IMF of the field population of the 30 Doradus super-association is determined using Wide Field Imager photometry. The cluster NGC 2070 and the OB association LH104 are also studied and used for comparison. The star-formation history of the 30~Doradus super-association appears to be characterized by a large increase in star-formation activity 10Myr to 20Myr ago. This seems to be the case across the whole eastern half of the LMC as demonstrated by the ages of stellar populations as far away as 30 Doradus and Shapley's Constellation III. Star-formation appears to be occurring at a constant rate in the field and in loose associations, and in bursts in the clusters. The field IMF is found to have almost the exact Salpeter slope in the range 7M_{sun}_<=M<=40M_{sun}_, at odds with previous claims. We find that, for objects with more complex star-formation histories, Be stars and selective incompleteness strongly affect the determination of the IMF for M>40M_{sun}_, naturally explaining the observed deviation of the high mass IMF slope from the Salpeter value.The present work supports the idea of a universal IMF.
- ID:
- ivo://CDS.VizieR/J/A+A/450/735
- Title:
- Effective temperatures and radii of stars
- Short Name:
- J/A+A/450/735
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper presents a method to determine effective temperatures, angular semi-diameters and bolometric corrections for population I and II FGK type stars based on V and 2MASS IR photometry. Accurate calibration is accomplished by using a sample of solar analogues, whose average temperature is assumed to be equal to the solar effective temperature of 5777K.