- 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/.
Number of results to display per page
Search Results
- 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/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.
- ID:
- ivo://CDS.VizieR/J/ApJ/711/284
- Title:
- Galaxy Zoo: AGN host galaxies
- Short Name:
- J/ApJ/711/284
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We use data from the Sloan Digital Sky Survey and visual classifications of morphology from the Galaxy Zoo project to study black hole growth in the nearby universe (z<0.05) and to break down the active galactic nucleus (AGN) host galaxy population by color, stellar mass, and morphology. We find that the black hole growth at luminosities L[OIII]>10^40^erg/s in early- and late-type galaxies is fundamentally different. AGN host galaxies as a population have a broad range of stellar masses (10^10^-10^11^M_{sun}_), reside in the green valley of the color-mass diagram and their central black holes have median masses around 10^6.5^M_{sun}_. However, by comparing early- and late-type AGN host galaxies to their non-active counterparts, we find several key differences: in early-type galaxies, it is preferentially the galaxies with the least massive black holes that are growing, while in late-type galaxies, it is preferentially the most massive black holes that are growing. At high-Eddington ratios (L/L_Edd_>0.1), the only population with a substantial fraction of AGNs are the low-mass green valley early-type galaxies.
- ID:
- ivo://CDS.VizieR/J/MNRAS/461/3663
- Title:
- Galaxy Zoo 2: new classification
- Short Name:
- J/MNRAS/461/3663
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The majority of galaxies in the local Universe exhibit spiral structure with a variety of forms. Many galaxies possess two prominent spiral arms, some have more, while others display a many-armed flocculent appearance. Spiral arms are associated with enhanced gas content and star formation in the discs of low-redshift galaxies, so are important in the understanding of star formation in the local universe. As both the visual appearance of spiral structure, and the mechanisms responsible for it vary from galaxy to galaxy, a reliable method for defining spiral samples with different visual morphologies is required. In this paper, we develop a new debiasing method to reliably correct for redshift-dependent bias in Galaxy Zoo 2, and release the new set of debiased classifications. Using these, a luminosity-limited sample of ~18000 Sloan Digital Sky Survey spiral galaxies is defined, which are then further sub-categorized by spiral arm number. In order to explore how different spiral galaxies form, the demographics of spiral galaxies with different spiral arm numbers are compared. It is found that whilst all spiral galaxies occupy similar ranges of stellar mass and environment, many-armed galaxies display much bluer colours than their two-armed counterparts. We conclude that two-armed structure is ubiquitous in star-forming discs, whereas many-armed spiral structure appears to be a short-lived phase, associated with more recent, stochastic star-formation activity.
- ID:
- ivo://CDS.VizieR/J/MNRAS/455/2440
- Title:
- Gal. 2D phot. decompositions in r, g & i bands
- Short Name:
- J/MNRAS/455/2440
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We extend the catalogue of two-dimensional, Point-Spread-Function-corrected de Vacouleurs, Sersic, de Vacouleurs+Exponential, and Sersic+Exponential fits of ~7x10^5^ galaxies presented in Meert+ (2015, J/MNRAS/446/3943) to include the g and i bands. Fits are analysed using the physically motivated flagging system presented in the original text, making adjustments for the differing signal to noise when necessary. We compare the fits in each of the g, r, and i bands. Fixed aperture magnitudes and colours are also provided for all galaxies.
- ID:
- ivo://CDS.VizieR/J/ApJ/676/944
- Title:
- GALEX and CFHTLS candidate tidal disruption events
- Short Name:
- J/ApJ/676/944
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present two luminous UV/optical flares from the nuclei of apparently inactive early-type galaxies at z=0.37 and 0.33 that have the radiative properties of a flare from the tidal disruption of a star. In this paper we report the second candidate tidal disruption event discovery in the UV by the GALEX Deep Imaging Survey and present simultaneous optical light curves from the CFHTLS Deep Imaging Survey for both UV flares.
- ID:
- ivo://CDS.VizieR/J/A+A/544/A101
- Title:
- GALEX observations of Herschel Reference Survey
- Short Name:
- J/A+A/544/A101
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present GALEX far-ultraviolet (FUV) and near-ultraviolet (NUV) as well as SDSS g, r, i photometry and structural parameters for the Herschel Reference Survey, a magnitude-, volume-limited sample of nearby galaxies in different environments. We use this unique dataset to investigate the ultraviolet (UV) structural scaling relations of nearby galaxies and to determine how the properties of the UV disk vary with atomic hydrogen content and environment.
- ID:
- ivo://CDS.VizieR/J/ApJ/733/74
- Title:
- GALEX - SDSS properties of local galaxies
- Short Name:
- J/ApJ/733/74
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present results of the first unbiased search for extended ultraviolet (XUV)-disk galaxies undertaken to determine the space density of such galaxies. Our sample contains 561 local (0.001<z<0.05) galaxies that lie in the intersection of available Galaxy Evolution Explorer (GALEX) deep imaging (exposure time >1.5x10^4^s) and Sloan Digital Sky Survey DR7 footprints. We explore modifications to the standard classification scheme for our sample that includes both disk- and bulge-dominated galaxies. Visual classification of each galaxy in the sample reveals an XUV-disk frequency of up to 20% for the most nearby portion of our sample. On average over the entire sample (out to z=0.05) the frequency ranges from a hard limit of 4%-14%. The GALEX imaging allows us to detect XUV disks beyond 100 Mpc. The XUV regions around XUV-disk galaxies are consistently bluer than the main bodies. We find a surprisingly high frequency of XUV emission around luminous red (NUV-r>5) and green valley (3<NUV-r<5) galaxies. The XUV-disk space density in the local universe is >(1.5-4.2)x10^-3^Mpc^-3^. Using the XUV emission as an indicator of recent gas accretion, we estimate that the cold gas accretion rate onto these galaxies is >(1.7-4.6)x10^-3^M_{sun}_/Mpc^3^/yr. The number of XUV disks in the green valley and the estimated accretion rate onto such galaxies points to the intriguing possibility that 7%-18% of galaxies in this population are transitioning away from the red sequence.