- ID:
- ivo://CDS.VizieR/VI/146
- Title:
- Galaxies in the Cosmic Dawn II simulation
- Short Name:
- VI/146
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Cosmic Dawn II (CoDa II) is a new, fully-coupled radiation-hydrodynamics simulation of cosmic reionization and galaxy formation and their mutual impact, to redshift z<6. With 4096^3^ particles and cells in a 94Mpc box, it is large enough to model global reionization and its feedback on galaxy formation while resolving all haloes above 10^8^M_{sun}_. Using the same hybrid CPU-GPU code RAMSES-CUDATON as CoDa I in Ocvirk et al. (2016MNRAS.463.1462O), CoDa II modified and re-calibrated the subgrid star-formation algorithm, making reionization end earlier, at z>~6, thereby better matching the observations of intergalactic Lyman-alpha opacity from quasar spectra and electron-scattering optical depth from cosmic microwave background fluctuations. CoDa II predicts a UV continuum luminosity function in good agreement with observations of high-z galaxies, especially at z=6. As in CoDa I, reionization feedback suppresses star formation in haloes below ~2x10^9^M_{sun}_, though suppression here is less severe, a possible consequence of modifying the star-formation algorithm. Suppression is environment-dependent, occurring earlier (later) in overdense (underdense) regions, in response to their local reionization times. Using a constrained realization of {LAMBDA}CDM constructed from galaxy survey data to reproduce the large-scale structure and major objects of the present-day Local Universe, CoDa II serves to model both global and local reionization. In CoDa II, the Milky Way and M31 appear as individual islands of reionization, i.e. they were not reionized by the progenitor of the Virgo cluster, nor by nearby groups, nor by each other. Description: The galaxy catalogs for redshifts z=10 down to z=6 (the simulation ended at z=5.8) are provided. Galaxies are identified as Friends-of-Friends dark matter haloes with a linking length ll=0.2. Stars are associated to each halo if they are within a sphere of radius r200. Magnitudes are computed using a BPASS stellar population model, as detailed in the article. No dust opacity is considered.
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Search Results
- ID:
- ivo://CDS.VizieR/J/MNRAS/395/1213
- Title:
- Galaxies in the field of MACS J1206.2-0847
- Short Name:
- J/MNRAS/395/1213
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We discuss the X-ray and optical properties of the massive galaxy cluster MACSJ1206.2-0847 (z=0.4385), discovered in the Massive Cluster Survey (MACS). Our Chandra observation of the system yields a total X-ray luminosity of 2.4x10^45^erg/s (0.1-2.4keV) and a global gas temperature of 11.6+/-0.7keV, very high values typical of MACS clusters. In both optical and X-ray images, MACSJ1206.2-0847 appears close to relaxed in projection, with a pronounced X-ray peak at the location of the brightest cluster galaxy (BCG); we interpret this feature as the remnant of a cold core. A spectacular giant gravitational arc, 15-arcsec in length, bright (V~21) and unusually red (R-K=4.3), is seen 20-arcsec west of the BCG; we measure a redshift of z=1.036 for the lensed galaxy. From our Hubble Space Telescope image of the cluster, we identify the giant arc and its counter image as a sevenfold imaged system. An excess of X-ray emission in the direction of the arc coincides with a mild galaxy overdensity and could be the remnant of a minor merger with a group of galaxies. We derive estimates of the total cluster mass as well as of the mass of the cluster core using X-ray, dynamical and gravitational-lensing techniques. For the mass enclosed by the giant arc (r<119kpc), our strong-lensing analysis based on Hubble Space Telescope imaging yields a very high value of 1.1x10^14^M_{sun}_, inconsistent with the much lower X-ray estimate of 0.5x10^14^M_{sun}_. Similarly, the virial estimate of 4x10^15^M_{sun}_ for the total cluster mass, derived from multi-object spectroscopy with Canada-France-Hawaii Telescope (CFHT) and the VLT of 38 cluster members, is significantly higher than the corresponding X-ray estimate of 1.7x10^15^M_{sun}_. We take the discrepancy between X-ray and other mass estimates to be indicative of pronounced substructure along the line of sight during an ongoing merger event, an interpretation that is supported by the system's very high velocity dispersion of 1580km/s.
- ID:
- ivo://CDS.VizieR/J/other/AstBu/73.124
- Title:
- Galaxies in the Local Supercluster band
- Short Name:
- J/other/AstBu/73
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We investigate the distribution and velocity field of galaxies situated in a band of 100x20 degrees centered on M87 and oriented along the Local supercluster plane. Our sample amounts 2158 galaxies with radial velocities less than 2000 km/s. Of them, 1119 galaxies (52%) have distance and peculiar velocity estimates. About 3/4 of early-type galaxies are concentrated within the Virgo cluster core, most of the late-type galaxies in the band locate outside the virial radius. Distribution of gas-rich dwarfs with M_HI_> M* looks to be insensitive to the Virgo cluster presence. Among 50 galaxy groups in the equatorial supercluster band 6 groups have peculiar velocities about 500-1000km/s comparable with virial motions in rich clusters. The most cryptic case is a flock of nearly 30 galaxies around NGC4278 (Coma I cloud), moving to us with the mean peculiar velocity of -840km/s. This cloud (or filament?) resides at a distance of 16.1Mpc from us and approximately 5Mpc away from the Virgo center. Galaxies around Virgo cluster exhibit Virgocentric infall with an amplitude of about 500 km/s. Assuming the spherically symmetric radial infall, we estimate the radius of the zero-velocity surface to be R0=(7.0+/-0.3)Mpc that yields the total mass of Virgo cluster to be (7.4+/-0.9)x10^14^ solar masses, in tight agreement with its virial mass estimates. We conclude that the Virgo outskirts does not contain significant amounts of dark mater beyond its virial core.
- ID:
- ivo://CDS.VizieR/J/A+AS/139/141
- Title:
- Galaxies in the Perseus Cluster
- Short Name:
- J/A+AS/139/141
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A new catalogue of 660 galaxies within a field of about 10 square degrees in the Perseus cluster region is presented. The catalogue contains accurate positions, isophotal magnitudes, angular radii, position angles, radial velocities, morphological types, and detailed informations on morphological peculiarities. If available, cross identifications and radial velocities are also given. The catalogue is estimated to be complete to a 25mag isophotal B magnitude of about 18.
- 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/437/1858
- Title:
- Galaxies in the RX J1347.5-1145 cluster
- Short Name:
- J/MNRAS/437/1858
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a revised strong lensing mass reconstruction of the galaxy cluster RX J1347.5-1145. The X-ray luminous cluster at redshift z=0.451 has already been studied intensively in the past. Based on information of two such previous (strong-) lensing studies by Halkola et al. (2008A&A...481...65H) and Bradac et al. (2008ApJ...681..187B), as well as by incorporating newly available data from the Cluster Lensing And Supernova survey with Hubble, we identified four systems of multiply lensed images (anew) in the redshift range 1.75<=z<=4.19. One multiple image system consists of in total eight multiply lensed images of the same source. The analysis based on a parametric mass model derived with the software GLAFIC suggests that the high image multiplicity is due to the source (z_phot_=4.19) being located on a so-called 'swallowtail' caustic. In addition to the parametric mass model, we also employed a non-parametric approach using the software pixelens in order to reconstruct the projected mass of the cluster using the same strong lensing data input. Both reconstructed mass models agree in revealing several mass components and a highly elliptic shape of the mass distribution. Furthermore, the projected mass inside, for example, a radius R~35arcsec~200kpc of the cluster for a source at redshift z=1.75 is M(<R)~(2.19^+0.01^_-0.02_)*10^14^M_{sun}_ as estimated by GLAFIC. Within the same radius pixelens predicts a mass of M(<R)~(2.47+/-0.01)*10^14^M_{sun}_which exceeds the GLAFIC estimate by ~13 per cent. The difference could be related to the fundamental degeneracy involved when constraining dark matter substructures with gravitationally lensed arcs.
- ID:
- ivo://CDS.VizieR/J/MNRAS/429/2264
- Title:
- Galaxies in the UMa cluster complex
- Short Name:
- J/MNRAS/429/2264
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A nearby friable cloud in Ursa Majoris contains 270 galaxies with radial velocities 500<V_LG_<1500km/s inside the area of RA=[11.0h,13.0h] and DE=[+40{deg},+60{deg}]. At present, 97 galaxies of them have individual distance estimates. We use these data to clarify the structure and kinematics of the UMa complex. According to Makarov & Karachentsev (2011MNRAS.412.2498M, Cat. J/MNRAS/412/2498), most of the UMa galaxies belong to seven bound groups, which have the following median parameters: velocity dispersion of 58k/s, harmonic projected radius of 300kpc, virial mass of 2x10^12^M{sun} and virial mass-to-K-band luminosity ratio of 27M{sun}/L{sun}. Almost a half of the UMa cloud population are gas-rich dwarfs (Ir, Im, BCD) with active star formation seen in the GALEX UV-survey. The UMa groups reside within 15-19Mpc from us, being just at the same distance as the Virgo cluster. The total virial mass of the UMa groups is 4x10^13^M{sun}, yielding the average density of dark matter in the UMa cloud to be {Omega}m=0.08, i.e. a factor of 3 lower than the cosmic average. This is despite the fact that the UMa cloud resides in a region of the Universe that is an apparent overdensity. A possible explanation for this is that most mass in the Universe lies in the empty space between clusters. Herewith, the mean distances and velocities of the UMa groups follow nearly undisturbed Hubble flow without a sign of the 'Z-wave' effect caused by infall towards a massive attractor. This constrains the total amount of dark matter between the UMa groups within the cloud volume.
- ID:
- ivo://CDS.VizieR/J/ApJ/816/98
- Title:
- Galaxies in X-ray clusters with DES. I. Stellar mass
- Short Name:
- J/ApJ/816/98
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using the science verification data of the Dark Energy Survey for a new sample of 106 X-ray selected clusters and groups, we study the stellar mass growth of bright central galaxies (BCGs) since redshift z~1.2. Compared with the expectation in a semi-analytical model applied to the Millennium Simulation, the observed BCGs become under-massive/under-luminous with decreasing redshift. We incorporate the uncertainties associated with cluster mass, redshift, and BCG stellar mass measurements into an analysis of a redshift-dependent BCG-cluster mass relation, m_*_{propto}(M_200_/1.5x10^14^M_{sun}_)^0.24+/-0.08^(1+z)^-0.19+/-0.34, and compare the observed relation to the model prediction. We estimate the average growth rate since z=1.0 for BCGs hosted by clusters of M_200,z_=10^13.8^M_{sun}_; at z=1.0: m_*,BCG_ appears to have grown by 0.13+/-0.11dex, in tension at the ~2.5{sigma} significance level with the 0.40 dex growth rate expected from the semi-analytic model. We show that the build-up of extended intracluster light after z=1.0 may alleviate this tension in BCG growth rates.
389. Galaxies near S1189
- ID:
- ivo://CDS.VizieR/J/MNRAS/406/2578
- Title:
- Galaxies near S1189
- Short Name:
- J/MNRAS/406/2578
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present radio images of a sample of six wide-angle tail (WAT) radio sources, identified in the Australia Telescope Large Area Survey 1.4-GHz radio survey, and new spectroscopic redshifts for four of these sources. These WATs are in the redshift range of 0.1469-0.3762, and we find evidence of galaxy overdensities in the vicinity of four of the WATs from either spectroscopic or photometric redshifts. We also present follow-up spectroscopic observations of the area surrounding the largest WAT, S1189, which is at a redshift of ~0.22. The spectroscopic observations, taken using the AAOmega spectrograph on the Anglo-Australian Telescope, show an overdensity of galaxies at this redshift. The galaxies are spread over an unusually large area of ~12Mpc with a velocity spread of ~4500km/s. This large-scale structure includes a highly asymmetric Fanaroff-Riley type I radio galaxy and also appears to host a radio relic. It may represent an unrelaxed system with different sub-structures interacting or merging with one another. We discuss the implications of these observations for future large-scale radio surveys.
- ID:
- ivo://CDS.VizieR/J/A+A/514/A60
- Title:
- Galaxies of J0454-0309 lensing fossil group
- Short Name:
- J/A+A/514/A60
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have discovered a strong lensing fossil group (J0454) projected near the well-studied cluster MS0451-0305. Using the large amount of available archival data, we compare J0454 to normal groups and clusters. A highly asymmetric image configuration of the strong lens enables us to study the substructure of the system. We used multicolour Subaru/Suprime-Cam and CFHT/Megaprime imaging, together with Keck spectroscopy to identify member galaxies. A VLT/FORS2 spectrum was taken to determine the redshifts of the brightest elliptical and the lensed arc. Using HST/ACS images, we determined the group's weak lensing signal and modelled the strong lens system. This is the first time that a fossil group is analysed with lensing methods. The X-ray luminosity and temperature were derived from XMM-Newton data.
