- ID:
- ivo://CDS.VizieR/J/ApJ/700/523
- Title:
- Galactic star clusters in SDSS. II. Colors.
- Short Name:
- J/ApJ/700/523
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We perform an extensive test of theoretical stellar models for main-sequence (MS) stars in ugriz, using cluster fiducial sequences obtained in the previous paper of this series. We generate a set of isochrones using the Yale Rotating Evolutionary Code with updated input physics, and derive magnitudes and colors in ugriz from MARCS model atmospheres. These models match cluster MSs over a wide range of metallicity within the errors of the adopted cluster parameters. However, we find a large discrepancy of model colors at the lower MS (T_eff_<~4500K) for clusters at and above solar metallicity. We also reach similar conclusions using the theoretical isochrones of Girardi et al. and Dotter et al., but our new models are generally in better agreement with the data. Using our theoretical isochrones, we also derive MS-fitting distances and turnoff ages for five key globular clusters, and demonstrate the ability to derive these quantities from photometric data in the Sloan Digital Sky Survey. In particular, we exploit multiple color indices (g-r, g-i, and g-z) in the parameter estimation, which allows us to evaluate internal systematic errors. Our distance estimates, with an error of {sigma}_(m-M)_=0.03-0.11mag for individual clusters, are consistent with Hipparcos-based subdwarf-fitting distances derived in the Johnson-Cousins or Stromgren photometric systems.
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Search Results
- ID:
- ivo://CDS.VizieR/J/MNRAS/446/3943
- Title:
- galaxies 2D phot. decompositions in SDSS-DR7
- Short Name:
- J/MNRAS/446/3943
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalogue of 2D, point spread function-corrected de Vacouleurs, Sersic, de Vacouleurs+Exponential, and Sersic+Exponential fits of ~7x10^5^ spectroscopically selected galaxies drawn from the Sloan Digital Sky Survey (SDSS) Data Release 7. Fits are performed for the SDSS r band utilizing the fitting routine galfit and analysis pipeline pymorph. We compare these fits to prior catalogues. Fits are analysed using a physically motivated flagging system. The flags suggest that more than 90 percent of two-component fits can be used for analysis. We show that the fits follow the expected behaviour for early and late galaxy types. The catalogues provide a robust set of structural and photometric parameters for future galaxy studies. We show that some biases remain in the measurements, e.g. the presence of bars significantly affect the bulge measurements although the bulge ellipticity may be used to separate barred and non-barred galaxies, and about 15 percent of bulges of two-component fits are also affected by resolution. The catalogues are available in electronic format. We also provide an interface for generating postage stamp images of the 2D model and residual as well as the 1D profile. These images can be generated for a user-uploaded list of galaxies on demand.
- ID:
- ivo://CDS.VizieR/J/MNRAS/467/4220
- Title:
- Galaxies inside 120 arcsec of HE 0435-1223
- Short Name:
- J/MNRAS/467/4220
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Based on spectroscopy and multiband wide-field observations of the gravitationally lensed quasar HE 0435-1223, we determine the probability distribution function of the external convergence {kappa}_ext_ for this system. We measure the under/overdensity of the line of sight towards the lens system and compare it to the average line of sight throughout the Universe, determined by using the CFHTLenS (The Canada France Hawaii Lensing Survey) as a control field. Aiming to constrain {kappa}_ext_ as tightly as possible, we determine under/overdensities using various combinations of relevant informative weighting schemes for the galaxy counts, such as projected distance to the lens, redshift and stellar mass. We then convert the measured under/overdensities into a {kappa}_ext_ distribution, using ray-tracing through the Millennium Simulation. We explore several limiting magnitudes and apertures, and account for systematic and statistical uncertainties relevant to the quality of the observational data, which we further test through simulations. Our most robust estimate of {kappa}_ext_ has a median value {kappa}^med^_ext_=0.004 and a standard deviation {sigma}_{kappa}_=0.025. The measured {sigma}_{kappa}_ corresponds to 2.5 per cent relative uncertainty on the time delay distance, and hence the Hubble constant H_0_ inferred from this system. The median {kappa}^med^_ext_ value varies by ~0.005 with the adopted aperture radius, limiting magnitude and weighting scheme, as long as the latter incorporates galaxy number counts, the projected distance to the main lens and a prior on the external shear obtained from mass modelling. This corresponds to just ~0.5 per cent systematic impact on H_0_. The availability of a well-constrained {kappa}_ext_ makes HE 0435-1223 a valuable system for measuring cosmological parameters using strong gravitational lens time delays.
- ID:
- ivo://CDS.VizieR/J/A+A/640/A30
- Title:
- Galaxies in the Perseus cluster field
- Short Name:
- J/A+A/640/A30
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We investigate the galaxies brighter than B~20 in the field of the Perseus cluster. The galaxies were selected on Schmidt CCD images in B and Halpha in combination with SDSS images. The survey field roughly covers the virial radius of the cluster. The galaxy sample is used for analysing cluster properties, such as radial profiles, indications of sub-structure, virial mass, and viral radius and is applied for a study of the cluster galaxy population with an emphasis on morphological types and peculiarities, star formation rates and active galactic nuclei.
- ID:
- ivo://CDS.VizieR/J/MNRAS/415/431
- Title:
- Galaxies with wide HI profiles
- Short Name:
- J/MNRAS/415/431
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We investigate the nature of objects in a complete sample of 28 galaxies selected from the first sky area fully covered by the Arecibo Legacy Fast ALFA (ALFALFA) survey, being well detected and having HI profiles wider than 550km/s. The selection does not use brightness, morphology or any other property derived from optical or other spectral bands. We investigate the degree of isolation, the morphology and other properties gathered or derived from open data bases and show that some objects have wide HI profiles probably because they are disturbed or are interacting, or might be confused in the ALFALFA beam.
- ID:
- ivo://CDS.VizieR/J/MNRAS/474/3875
- Title:
- Galaxy And Mass Assembly (GAMA): DR3
- Short Name:
- J/MNRAS/474/3875
- Date:
- 19 Jan 2022 09:03:58
- Publisher:
- CDS
- Description:
- We describe data release 3 (DR3) of the Galaxy And Mass Assembly (GAMA) survey. The GAMA survey is a spectroscopic redshift and multiwavelength photometric survey in three equatorial regions each of 60.0deg^2^ (G09, G12, and G15), and two southern regions of 55.7deg^2^ (G02) and 50.6deg^2^ (G23). DR3 consists of: the first release of data covering the G02 region and of data on H-ATLAS (Herschel - Astrophysical Terahertz Large Area Survey) sources in the equatorial regions; and updates to data on sources released in DR2. DR3 includes 154809 sources with secure redshifts across four regions. A subset of the G02 region is 95.5 per cent redshift complete to r<19.8mag over an area of 19.5deg^2^, with 20086 galaxy redshifts, that overlaps substantially with the XXL survey (X-ray) and VIPERS (redshift survey). In the equatorial regions, the main survey has even higher completeness (98.5 per cent), and spectra for about 75 per cent of H-ATLAS filler targets were also obtained. This filler sample extends spectroscopic redshifts, for probable optical counterparts to H-ATLAS submillimetre sources, to 0.8mag deeper (r<20.6mag) than the GAMA main survey. There are 25814 galaxy redshifts for H-ATLAS sources from the GAMA main or filler surveys. GAMA DR3 is available at the survey website (www.gama-survey.org/dr3/).
- ID:
- ivo://CDS.VizieR/J/MNRAS/452/2087
- Title:
- Galaxy And Mass Assembly (GAMA): DR2
- Short Name:
- J/MNRAS/452/2087
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Galaxy And Mass Assembly (GAMA) survey is one of the largest contemporary spectroscopic surveys of low redshift galaxies. Covering an area of ~286deg^2^ (split among five survey regions) down to a limiting magnitude of r<19.8mag, we have collected spectra and reliable redshifts for 238000 objects using the AAOmega spectrograph on the Anglo-Australian Telescope. In addition, we have assembled imaging data from a number of independent surveys in order to generate photometry spanning the wavelength range 1nm-1m. Here, we report on the recently completed spectroscopic survey and present a series of diagnostics to assess its final state and the quality of the redshift data. We also describe a number of survey aspects and procedures, or updates thereof, including changes to the input catalogue, redshifting and re-redshifting, and the derivation of ultraviolet, optical and near-infrared photometry. Finally, we present the second public release of GAMA data. In this release, we provide input catalogue and targeting information, spectra, redshifts, ultraviolet, optical and near-infrared photometry, single-component Sersic fits, stellar masses, H{alpha}-derived star formation rates, environment information, and group properties for all galaxies with r<19.0mag in two of our survey regions, and for all galaxies with r<19.4mag in a third region (72225 objects in total). The data base serving these data is available at http://www.gama-survey.org/.
- ID:
- ivo://CDS.VizieR/J/MNRAS/413/971
- Title:
- Galaxy And Mass Assembly (GAMA) DR1
- Short Name:
- J/MNRAS/413/971
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Galaxy and Mass Assembly (GAMA) survey has been operating since 2008 February on the 3.9-m Anglo-Australian Telescope using the AAOmega fibre-fed spectrograph facility to acquire spectra with a resolution of R~1300 for 120862 Sloan Digital Sky Survey selected galaxies. The target catalogue constitutes three contiguous equatorial regions centred at 9h (G09), 12h (G12) and 14.5h (G15) each of 12x4deg^2^ to limiting fluxes of r_pet_<19.4, r_pet_<19.8 and r_pet_<19.4 mag, respectively (and additional limits at other wavelengths). Spectra and reliable redshifts have been acquired for over 98 per cent of the galaxies within these limits. Here we present the survey footprint, progression, data reduction, redshifting, re-redshifting, an assessment of data quality after 3yr, additional image analysis products (including ugrizYJHK photometry, Sersic profiles and photometric redshifts), observing mask and construction of our core survey catalogue (GamaCore). From this we create three science-ready catalogues: GamaCoreDR1 for public release, which includes data acquired during year 1 of operations within specified magnitude limits (2008 February to April); GamaCoreMainSurvey containing all data above our survey limits for use by the GAMA Team and collaborators; and GamaCoreAtlasSV containing year 1, 2 and 3 data matched to Herschel-ATLAS science demonstration data. These catalogues along with the associated spectra, stamps and profiles can be accessed via the GAMA website: http://www.gama-survey.org/
- ID:
- ivo://CDS.VizieR/J/AJ/141/88
- Title:
- Galaxy cluster environments of radio sources
- Short Name:
- J/AJ/141/88
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using the Sloan Digital Sky Survey (SDSS) and the Faint Images of the Radio Sky at Twenty Centimeters (FIRST) catalogs, we examined the optical environments around double-lobed radio sources. Previous studies have shown that multi-component radio sources exhibiting some degree of bending between components are likely to be found in galaxy clusters. Often this radio emission is associated with a cD-type galaxy at the center of a cluster. We cross-correlated the SDSS and FIRST catalogs and measured the richness of the cluster environments surrounding both bent and straight multi-component radio sources. This led to the discovery and classification of a large number of galaxy clusters out to a redshift of z~0.5.
- ID:
- ivo://CDS.VizieR/J/ApJ/736/21
- Title:
- Galaxy clusters optical catalog from AMF on SDSS DR6
- Short Name:
- J/ApJ/736/21
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a new cluster catalog extracted from the Sloan Digital Sky Survey Data Release 6 (SDSS DR6) using an adaptive matched filter (AMF) cluster finder. We identify 69,173 galaxy clusters in the redshift range 0.045<=z<0.78 in 8420deg^2^ of the sky. We provide angular position, redshift, richness, core, and virial radii estimates for these clusters, as well as an error analysis for each of these quantities. We also provide a catalog of more than 205,000 galaxies representing the three brightest galaxies in the r band which are possible brightest cluster galaxy (BCG) candidates. We show basic properties of the BCG candidates and study how their luminosity scales in redshift and cluster richness. We compare our catalog with the maxBCG and GMBCG catalogs, as well as with that of Wen et al. We match between 30% and 50% of clusters between catalogs over all overlapping redshift ranges. We find that the percentage of matches increases with the richness for all catalogs. We cross match the AMF catalog with available X-ray data in the same area of the sky and find 539 matches, 119 of which with temperature measurements. We present scaling relations between optical and X-ray properties and cluster center comparison.
