- ID:
- ivo://CDS.VizieR/J/MNRAS/446/683
- Title:
- Free-form lensing grid solution for A1689
- Short Name:
- J/MNRAS/446/683
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We examine Abell 1689 non-parametrically, combining strongly lensed Hubble Space Telescope images and weak distortions from wider field Subaru imaging. Our model incorporates member galaxies to improve the lens solution. By adding luminosity-scaled member galaxy deflections to our smooth grid, we can derive meaningful solutions with sufficient accuracy to permit the identification of our own strongly lensed images, so our model becomes self-consistent. We identify 11 new multiply lensed system candidates and clarify previously ambiguous cases, in the deepest optical and near-infrared data to date from Hubble and Subaru. Our improved spatial resolution brings up new features not seen when the weak and strong lensing effects are used separately, including clumps and filamentary dark matter around the main halo. Our treatment means we can obtain an objective mass ratio between the cluster and galaxy components. We find a typical mass-to-light ratios of M/L_B_=21+/-14 inside the r<1arcmin region. Our model independence means we can objectively evaluate the competitiveness of stacking cluster lenses for defining the geometric lensing-distance-redshift relation in a model-independent way.
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- ID:
- ivo://CDS.VizieR/J/MNRAS/369/1334
- Title:
- FSVS Cluster Catalogue
- Short Name:
- J/MNRAS/369/1334
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We describe a large sample of 598 galaxy clusters and rich groups discovered in the data of the Faint Sky Variability Survey (FSVS). The clusters have been identified using a fully automated, semiparametric technique based on a maximum likelihood approach applied to Voronoi tessellation, and enhanced by colour discrimination. The sample covers a wide range of richness, has a density of ~28 clusters/deg^2^, and spans a range of estimated redshifts of 0.05<z<0.9 with mean <z>=0.345. Assuming the presence of a cluster red sequence, the uncertainty of the estimated cluster redshifts is assessed to be {sigma}~0.03. Containing over 100 clusters with z>0.6, the catalogue contributes substantially to the current total of optically selected, intermediate-redshift clusters, and complements the existing, usually X-ray selected, samples. The FSVS fields are accessible for observation throughout the whole year, making them particularly suited for large follow-up programmes. The construction of this FSVS Cluster Catalogue completes a fundamental component of our continuing programmes to investigate the environments of quasars and the chemical evolution of galaxies. We publish here the list of all clusters with their basic parameters, and discuss some illustrative examples in more detail. The full FSVS Cluster Catalogue, together with images and lists of member galaxies etc., will be issued as part of the 'NOAO (National Optical Astronomy Observatories) data products', and accessible at http://www.noao.edu/dpp/ . We describe the format of these data and access to them.
- ID:
- ivo://CDS.VizieR/J/A+AS/140/327
- Title:
- Fundamental plane galaxies redshifts
- Short Name:
- J/A+AS/140/327
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Radial velocities and central velocity dispersions are derived for 238 E/S0 galaxies from medium-resolution spectroscopy. New spectroscopic data have been obtained as part of a study of the Fundamental Plane distances and peculiar motions of early-type galaxies in three selected directions of the South Equatorial Strip, undertaken in order to investigate the reality of large-scale streaming motion; results of this study have been reported in Mueller et al. (1998ApJ...507L.105M). The new APM South Equatorial Strip Catalog (-17.5deg<{delta}<+2.5deg) (Raychaudhury & Lynden-Bell, 2000) was used to select the sample of field galaxies in three directions: (1) 15h10-16h10; (2) 20h30-21h50; (3) 00h10-01h30. The spectra obtained have a median S/N per {AA} of 23, an instrumental resolution (FWHM) of ~4{AA}, and the spectrograph resolution (dispersion) is ~100km/s. The Fourier cross-correlation method was used to derive the radial velocities and velocity dispersions. The velocity dispersions have been corrected for the size of the aperture and for the galaxy effective radius. Comparisons of the derived radial velocities with data from the literature show that our values are accurate to 40km/s. A comparison with results from Jorgensen et al. (1995MNRAS.276.1341J) shows that the derived central velocity dispersion have an rms scatter of 0.036 in log{sigma}. There is no offset relative to the velocity dispersions of Davies et al. (1987ApJS...64..581D).
- ID:
- ivo://CDS.VizieR/J/MNRAS/467/3140
- Title:
- Galaxies angular momentum evolution
- Short Name:
- J/MNRAS/467/3140
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a MUSE (Multi-Unit Spectroscopic Explorer) and KMOS (K-band Multi-Object Spectrograph) dynamical study 405 star-forming galaxies at redshift z=0.28-1.65 (median redshift <z>=0.84). Our sample is representative of the star-forming 'main sequence', with star formation rates of SFR=0.1-30M_{sun}_/yr and stellar masses M*=10^8^-10^11^M_{sun}_. For 49+/-4 per cent of our sample, the dynamics suggest rotational support, 24+/-3 per cent are unresolved systems and 5+/-2 per cent appear to be early-stage major mergers with components on 8-30kpc scales. The remaining 22+/-5 per cent appear to be dynamically complex, irregular (or face-on systems). For galaxies whose dynamics suggest rotational support, we derive inclination-corrected rotational velocities and show that these systems lie on a similar scaling between stellar mass and specific angular momentum as local spirals with j*=J/M*{prop.to}M*^2/3^ but with a redshift evolution that scales as j*{prop.to}M*^2/3^(1+z)^-1^. We also identify a correlation between specific angular momentum and disc stability such that galaxies with the highest specific angular momentum (log(j*/M*^2/3^)>2.5) are the most stable, with Toomre Q=1.10+/-0.18, compared to Q=0.53+/-0.22 for galaxies with log(j*/M*^2/3^)<2.5. At a fixed mass, the Hubble Space Telescope morphologies of galaxies with the highest specific angular momentum resemble spiral galaxies, whilst those with low specific angular momentum are morphologically complex and dominated by several bright star-forming regions. This suggests that angular momentum plays a major role in defining the stability of gas discs: at z~1, massive galaxies that have discs with low specific angular momentum are globally unstable, clumpy and turbulent systems. In contrast, galaxies with high specific angular momentum have evolved into stable discs with spiral structure where star formation is a local (rather than global) process.
- ID:
- ivo://CDS.VizieR/J/other/AstBu/72.111
- Title:
- Galaxies in Hercules-Bootes region
- Short Name:
- J/other/AstBu/72
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We consider a sample of 412 galaxies with radial velocities V_LG_<2500km/s situated in the sky region of RA=13.0h-19.0h, Dec=+10{deg}...+40{deg} between the Local Void and the Supergalactic plane. One hundred and eighty-one of them have individual distance estimates. Peculiar velocities of the galaxies as a function of Supergalactic latitude SGB show signs of Virgocentric infall at SGB<10{deg} and motion from the Local Void at SGB>60{deg}. A half of the Hercules-Bootes galaxies belong to 17 groups and 29 pairs, with the richest group around NGC5353. A typical group is characterized by the velocity dispersion of 67km/s, the harmonic radius of 182kpc, the stellar mass of 4.3x10^10^M_{sun}_ and the virial- to-stellar mass ratio of 32. The binary galaxies have the mean radial velocity difference of 37km/s, the projected separation of 96kpc, the mean integral stellar mass of 2.6x10^9^M_{sun}_ and the mean virial-to-stellar mass ratio of about 8. The total dark-matter-to-stellar mass ratio in the considered sky region amounts to 37 being almost the same as that in the Local Volume.
- ID:
- ivo://CDS.VizieR/J/other/AstBu/70.1
- Title:
- Galaxies in Leo/Cnc region
- Short Name:
- J/other/AstBu/70
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In the region of the sky limited by the coordinates RA=7.0h...12.0h, Dec=0{deg}...+20{deg} and extending from the Virgo Cluster to the South Pole of the Local Supercluster, we consider the data on the galaxies with radial velocities V_LG_<~2000km/s. For 290 among them, we determine individual distances and peculiar velocities. In this region, known as the local velocity anomaly zone, there are 23 groups and 20 pairs of galaxies for which the estimates of virial/orbital masses are obtained. A nearby group around NGC3379 = Leo I and NGC3627 as well as the Local Group show the motion from the Local Void in the direction of Leo cloud with a characteristic velocity of about 400 km/s. Another rich group of galaxies around NGC3607 reveals peculiar velocity of about -420km/s in the frame of reference related with the cosmic background radiation. A peculiar scattered association of dwarf galaxies Gemini Flock at a distance of 8Mpc has the radial velocity dispersion of only 20km/s and the size of approximately 0.7Mpc. The virial mass estimate for it is 300 times greater than the total stellar mass. The ratio of the sum of virial masses of groups and pairs in the Leo/Can region to the sum of stellar masses of the galaxies contained in them equals 26, which is equivalent to the local average density {Omega}_m(local)_=0.074, which is 3-4 times smaller than the global average density of matter.
- ID:
- ivo://CDS.VizieR/J/MNRAS/276/689
- Title:
- Galaxies in SGP region
- Short Name:
- J/MNRAS/276/689
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the data from an extensive, moderately deep (b_J_~19.5) spectroscopic survey of ~600 galaxies within four regions of the sky located near the South Galactic Pole. About 75% of the measured galaxies are in an approximately 3x1.5sq.deg region dominated by the rich cluster of galaxies Klemola 44 (Abell 4038). The other three small areas cover about 1sq.deg each. Here, we discuss in detail the observing and data reduction strategies, and the completeness of and errors in the measured redshifts. The data collected are being used for: (i) a study of the large-scale redshift distribution of the galaxies in each field, and (ii) a thorough dynamical investigation of Klemola 44. Results from these analyses will be presented in forthcoming papers.
- ID:
- ivo://CDS.VizieR/J/MNRAS/404/749
- Title:
- Galaxies in the field of B2108+213
- Short Name:
- J/MNRAS/404/749
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The gravitational lens system CLASS B2108+213 has two radio-loud lensed images separated by 4.56 arcsec. The relatively large image separation implies that the lensing is caused by a group of galaxies. In this paper, new optical imaging and spectroscopic data for the lensing galaxies of B2108+213 and the surrounding field galaxies are presented. These data are used to investigate the mass and composition of the lensing structure.
- 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/RAA/11.245
- Title:
- Galaxies in the field of RX J0054.0-2823
- Short Name:
- J/other/RAA/11.2
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present galactic spectroscopic data from a pencil beam of 10.75'x7.5' centered on the X-ray cluster RXJ0054.0-2823 at z=0.29. We study the spectral evolution of galaxies from z=1 down to the cluster redshift in a magnitude-limited sample at R<=23, for which the statistical properties of the sample are well understood. We divide emission-line galaxies into star-forming galaxies, Low Ionization Nuclear Emission line Regions (LINERs), and Seyferts by using emission-line ratios of [OII],H{beta}, and [OIII], and derive stellar fractions from population synthesis models. We focus our analysis on absorption and low-ionization galaxies.
