- ID:
- ivo://CDS.VizieR/J/MNRAS/414/3052
- Title:
- HST/ACS Coma Cluster Survey. VI.
- Short Name:
- J/MNRAS/414/3052
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using deep, high-spatial-resolution imaging from the Hubble Space Telescope/Advanced Camera for Surveys (HST/ACS) Coma Cluster Treasury Survey, we determine colour profiles of early-type galaxies in the Coma cluster. From 176 galaxies brighter than MF814W(AB)=-15mag that are either spectroscopically confirmed members of Coma or identified by eye as likely members from their low surface brightness, data are provided for 142 early-type galaxies. Typically, colour profiles are linear against log (R), sometimes with a nuclear region of distinct, often bluer colour associated with nuclear clusters. Colour gradients are determined for the regions outside the nuclear components. We find that almost all colour gradients are negative, both for elliptical and for lenticular galaxies. Most likely, earlier studies that report positive colour gradients in dwarf galaxies are affected by the bluer colours of the nuclear clusters, underlining that high-resolution data are essential to disentangle the colour properties of the different morphological components in galaxies. Colour gradients of dwarf galaxies form a continuous sequence with those of elliptical galaxies, becoming shallower towards fainter magnitudes. Interpreting the colours as metallicity tracers, our data suggest that dwarfs as well as giant early-type galaxies in the Coma cluster are less metal rich in their outer parts. We do not find evidence for environmental influence on the gradients, although we note that most of our galaxies are found in the central regions of the cluster. For a subset of galaxies with known morphological types, S0 galaxies have less steep gradients than elliptical galaxies.
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Search Results
- ID:
- ivo://CDS.VizieR/J/MNRAS/444/268
- Title:
- HST Frontier Fields clusters
- Short Name:
- J/MNRAS/444/268
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Extending over three Hubble Space Telescope (HST) cycles, the Hubble Frontier Fields (HFF) initiative constitutes the largest commitment ever of HST time to the exploration of the distant Universe via gravitational lensing by massive galaxy clusters. Here, we present models of the mass distribution in the six HFF cluster lenses, derived from a joint strong- and weak-lensing analysis anchored by a total of 88 multiple-image systems identified in existing HST data. The resulting maps of the projected mass distribution and of the gravitational magnification effectively calibrate the HFF clusters as gravitational telescopes. Allowing the computation of search areas in the source plane, these maps are provided to the community to facilitate the exploitation of forthcoming HFF data for quantitative studies of the gravitationally lensed population of background galaxies. Our models of the gravitational magnification afforded by the HFF clusters allow us to quantify the lensing-induced boost in sensitivity over blank-field observations and predict that galaxies at z>10 and as faint as m(AB)=32 will be detectable, up to 2mag fainter than the limit of the Hubble Ultra Deep Field.
- ID:
- ivo://CDS.VizieR/J/PASP/106/646
- Title:
- HST quasar absorption-line key project. VIII.
- Short Name:
- J/PASP/106/646
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present an analysis of CCD images (obtained at the Palomar 1.5m telescope) of more than 100 quasars; many of the objects have been or will be observed in the HST Key Project Quasar Absorption-Line Survey. The data set consists of B, g, and i photometry of 117 quasars and deeper g (limiting magnitude of ~22) images of 101 quasar fields. Positions accurate to ~1", measured with the Space Telescope Science Institute's Astrometric Support Program, are listed for all of the quasars in this study. Positions, magnitudes, and classifications of stars and galaxies located within ~100" of the quasars are given for all of the deep g data. The positions of the stars and galaxies relative to the quasar are accurate to ~0.5". The results presented here can be used to prepare spectroscopic programs designed to obtain redshifts of galaxies in the fields of these quasars.
- ID:
- ivo://CDS.VizieR/J/MNRAS/413/80
- Title:
- Hubble Space Telescope GOODS NICMOS Survey
- Short Name:
- J/MNRAS/413/80
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the details and early results from a deep near-infrared survey utilizing the NICMOS instrument on the Hubble Space Telescope centred around massive M*>10^11^M_{sun}_ galaxies at 1.7<z<2.9 found within the Great Observatories Origins Deep Survey (GOODS) fields North and South. The GOODS NICMOS Survey (GNS) was designed to obtain deep F160W (H-band) imaging of 80 of these massive galaxies and other colour-selected objects such as Lyman-break dropouts, BzK objects, distant red galaxies (DRGs), extremely red objects (EROs), Spitzer-selected EROs, BX/BM galaxies, as well as flux-selected submillimetre galaxies. We present in this paper details of the observations, our sample selection, as well as a description of the properties of the massive galaxies found within our survey fields. This includes photometric redshifts, rest-frame colours and stellar masses. We furthermore provide an analysis of the selection methods for finding massive galaxies at high redshifts, including colour-selection methods and how galaxy populations selected through these colour methods overlap.
- ID:
- ivo://CDS.VizieR/J/MNRAS/449/1753
- Title:
- I-band light curves of SNe II from OGLE-IV
- Short Name:
- J/MNRAS/449/1753
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We study a sample of 11 Type II supernovae (SNe) discovered by the OGLE-IV survey. All objects have well-sampled I-band light curves, and at least one spectrum. We find that two or three of the 11 SNe have a declining light curve, and spectra consistent with other SNe II-L, while the rest have plateaus that can be as short as 70 d, unlike the 100 d typically found in nearby galaxies. The OGLE SNe are also brighter, and show that magnitude-limited surveys find SNe that are different than usually found in nearby galaxies. We discuss this sample in the context of understanding Type II SNe as a class and their suggested use as standard candles.
- ID:
- ivo://CDS.VizieR/J/MNRAS/455/1796
- Title:
- IDEOS redshift catalogue
- Short Name:
- J/MNRAS/455/1796
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This is the first of a series of papers on the Infrared Database of Extragalactic Observables from Spitzer (IDEOS). In this work, we describe the identification of optical counterparts of the infrared sources detected in Spitzer Infrared Spectrograph (IRS) observations and the acquisition and validation of redshifts. The IDEOS sample includes all the spectra from the Cornell Atlas of Spitzer/IRS Sources (CASSIS, Lebouteiller et al., 2011ApJS..196....8L, 2015ApJS..218...21L) of galaxies beyond the Local Group. Optical counterparts were identified from correlation of the extraction coordinates with the NASA Extragalactic Database (NED). To confirm the optical association and validate NED redshifts, we measure redshifts with unprecedented accuracy on the IRS spectra ({sigma}({Delta}z/(1+z))~0.0011) by using an improved version of the maximum combined pseudo-likelihood method (MCPL). We perform a multistage verification of redshifts that considers alternate NED redshifts, the MCPL redshift, and visual inspection of the IRS spectrum. The statistics is as follows: the IDEOS sample contains 3361 galaxies at redshift 0<z<6.42 (mean: 0.48, median: 0.14). We confirm the default NED redshift for 2429 sources and identify 124 with incorrect NED redshifts. We obtain IRS-based redshifts for 568 IDEOS sources without optical spectroscopic redshifts, including 228 with no previous redshift measurements. We provide the entire IDEOS redshift catalogue in machine-readable formats. The catalogue condenses our compilation and verification effort, and includes our final evaluation on the most likely redshift for each source, its origin, and reliability estimates.
- ID:
- ivo://CDS.VizieR/J/MNRAS/398/109
- Title:
- Imperial IRAS-FSC redshift catalogue (IIFSCz)
- Short Name:
- J/MNRAS/398/109
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a new catalogue, the Imperial IRAS-FSC Redshift Catalogue (IIFSCz), of 60303 galaxies selected at 60um from the IRAS Faint Source Catalogue (FSC). The IIFSCz consists of accurate position, optical, near-infrared and/or radio identifications, spectroscopic redshift (if available) or photometric redshift (if possible), predicted far-infrared (FIR) and submillimetre (submm) fluxes ranging from 12 to 1380um based upon the best-fitting infrared template. About 55% of the galaxies in the IIFSCz have spectroscopic redshifts, and a further 20% have photometric redshifts obtained through either the training set or the template-fitting method. For S(60)>0.36Jy, the 90% completeness limit of the FSC, 90% of the sources have either spectroscopic or photometric redshifts. Scientific applications of the IIFSCz include validation of current and forthcoming infrared and submm/mm surveys such as AKARI, Planck and Herschel, follow-up studies of rare source populations, large-scale structure and galaxy bias, local multiwavelength luminosity functions and source counts. The catalogue is publicly available at http://astro.imperial.ac.uk/~mrr/fss/.
- ID:
- ivo://CDS.VizieR/J/MNRAS/405/2302
- Title:
- Improved redshifts for SDSS quasar spectra
- Short Name:
- J/MNRAS/405/2302
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A systematic investigation of the relationship between different redshift estimation schemes for more than 91000 quasars in the Sloan Digital Sky Survey (SDSS) Data Release 6 is presented. The publicly available SDSS quasar redshifts are shown to possess systematic biases of {Delta}z/(1+z)>=0.002 (600km/s) over both small ({delta}z~=0.1) and large ({delta}z~=1) redshift intervals. Empirical relationships between redshifts based on (i) CaII H&K host galaxy absorption, (ii) quasar [OII] {lambda}{lambda}3728, (iii) [OIII] {lambda}{lambda} 4960, 5008 emission and (iv) cross-correlation (with a master-quasar template) that includes, at increasing quasar redshift, the prominent MgII {lambda}{lambda} 2799, CIII] {lambda}{lambda} 1908 and CIV {lambda}{lambda} 1549 emission lines are established as a function of quasar redshift and luminosity. New redshifts in the resulting catalogue possess systematic biases, a factor of ~=20 lower compared to the SDSS redshift values; systematic effects are reduced to the level of {Delta}z/(1+z) (30km/s) per unit redshift or <=2.5x10^-5^ per unit absolute magnitude. Redshift errors, including components due both to internal reproducibility and to the intrinsic quasar-to-quasar variation among the population, are available for all quasars in the catalogue. The improved redshifts and their associated errors have wide applicability in areas such as quasar absorption outflows, quasar clustering, quasar-galaxy clustering and proximity-effect determinations.
- ID:
- ivo://CDS.VizieR/J/A+AS/104/529
- Title:
- IRAS galaxies behind the Milky Way
- Short Name:
- J/A+AS/104/529
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We made a search for IRAS galaxies behind the Northern Milky Way by infrared selection using IRAS Point Source Catalog and visual inspection on POSS (Palomar Observatory Sky Survey) paper prints, and carried out a redshift survey of the identified objects. This paper presents a catalog of 649 IRAS galaxies with f_60_>=0.6Jy between l=150deg and 240deg at |b|<=15deg, which contains 254 newly identified galaxies and 188 newly measured radial velocities. Due to galactic extinction, our sample is a lower limit sample of the flux limited sample of IRAS galaxies, but it can give some information on the distribution of galaxies in the region perpendicular to the Supergalactic Plane. We confirm two regions with enhanced density at l~160deg, cz~5000km/s and l~190deg, cz~5000km/s and at least two possible voids.
- ID:
- ivo://CDS.VizieR/VII/185
- Title:
- IRAS 1.2 Jy IRAS Redshift Survey
- Short Name:
- VII/185
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This is an explanation of the redshift survey of Fisher, Huchra, Strauss, Davis, Yahil and Schlegel; the data set is described in full in ApJ 361, 49 (1990). The data for the brighter half are included in ApJ Supp 1992, 83, 29; the data for the fainter half are included in a paper submitted for publication to the Astrophysical Journal Supplement. The survey contains 9897 objects selected from the IRAS database according to the criteria listed in that paper, briefly: F60 > 1.2 Jy; F60^2^ > F12 f25; |b| > 5; high source density flag at 60 microns not raised. Thus, the file consists of both galaxies and Galaxian contaminants; this is explained below. The sample contains ~5320 galaxies, and 14 objects without id's at the present time.
