- ID:
- ivo://CDS.VizieR/J/MNRAS/427/1666
- Title:
- Massive galaxies in CANDELS-UDS field
- Short Name:
- J/MNRAS/427/1666
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have used high-resolution, Hubble Space Telescope, near-infrared imaging to conduct a detailed analysis of the morphological properties of the most massive galaxies at high redshift, modelling the WFC3/IR H_160_-band images of the =~200 galaxies in the CANDELS-UDS field with photometric redshifts 1<z<3, and stellar masses M_*_>10^11^M_{sun}_. We have explored the results of fitting single-Sersic and bulge+disc models, and have investigated the additional errors and potential biases introduced by uncertainties in the background and the on-image point spread function.
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- ID:
- ivo://CDS.VizieR/J/MNRAS/382/109
- Title:
- Massive galaxies in Extended Groth Strip
- Short Name:
- J/MNRAS/382/109
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using the combined capabilities of the large near-infrared Palomar/DEEP-2 survey, and the superb resolution of the Advanced Camera for Surveys HST camera, we explore the size evolution of 831 very massive galaxies (M*>=10^11^h^-2^_70_M_{sun}_) since z~2. We split our sample according to their light concentration using the Sersic index n. At a given stellar mass, both low (n<2.5) and high (n>2.5) concentrated objects were much smaller in the past than their local massive counterparts. This evolution is particularly strong for the highly concentrated (spheroid like) objects. At z~1.5, massive spheroid-like objects were a factor of 4(+/-0.4) smaller (i.e. almost two orders of magnitudes denser) than those we see today. These small sized, high-mass galaxies do not exist in the nearby Universe, suggesting that this population merged with other galaxies over several billion years to form the largest galaxies we see today.
- ID:
- ivo://CDS.VizieR/J/A+A/646/A83
- Title:
- 12 massive lensing clusters MUSE observations
- Short Name:
- J/A+A/646/A83
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Spectroscopic surveys of massive galaxy clusters reveal the properties of faint background galaxies thanks to the magnification provided by strong gravitational lensing. We present a systematic analysis of integral-field- spectroscopy observations of 12 massive clusters, conducted with the Multi Unit Spectroscopic Explorer (MUSE). All data were taken under very good seeing conditions (~0.6") in effective exposure times between two and 15 hrs per pointing, for a total of 125 hrs. Our observations cover a total solid angle of ~23-arcmin^2^ in the direction of clusters, many of which were previously studied by the MAssive Clusters Survey (MACS), Frontier Fields (FFs), Grism Lens-Amplified Survey from Space (GLASS) and Cluster Lensing And Supernova survey with Hubble (CLASH) programmes. The achieved emission line detection limit at 5sigma for a point source varies between (0.77-1.5)x10^-18^erg/s/cm^2^ at 7000{AA}. We present our developed strategy to reduce these observational data, detect continuum sources and line emitters in the datacubes, and determine their redshifts. We constructed robust mass models for each cluster to further confirm our redshift measurements using strong-lensing constraints, and identified a total of 312 strongly lensed sources producing 939 multiple images. The final redshift catalogues contain more than 3300 robust redshifts, of which 40% are for cluster members and ~30% are for lensed Lyman-alpha emitters. Fourteen percent of all sources are line emitters that are not seen in the available HST images, even at the depth of the FFs (~29 AB). We find that the magnification distribution of the lensed sources in the high- magnification regime (mu=2-25) follows the theoretical expectation of N(z){prop.to}mu^-2^. The quality of this dataset, number of lensed sources, and number of strong-lensing constraints enables detailed studies of the physical properties of both the lensing cluster and the background galaxies. The full data products from this work, including the datacubes, catalogues, extracted spectra, ancillary images, and mass models, are made available to the community.
- ID:
- ivo://CDS.VizieR/J/MNRAS/441/203
- Title:
- Massive quiescent ETG in clusters
- Short Name:
- J/MNRAS/441/203
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We analyse the mass-size relation of ~400 quiescent massive ETGs (M*/M_{sun}_>3x10^10^) hosted by massive clusters (M200~2-7x10^14^M_{sun}_) at 0.8<z<1.5, compared to those found in the field at the same epoch. Size is parametrized using the mass-normalized B-band rest-frame size, {gamma}=R_e_/M_11_^0.57^. We find that the {gamma} distributions in both environments peak at the same position, but the distributions in clusters are more skewed towards larger sizes. This tail induces average sizes ~ 30-40 percent larger for cluster galaxies than for field galaxies of similar stellar mass, while the median sizes are statistically the same with a difference of ~10+/-10%. Since this size difference is not observed in the local Universe, the evolution of average galaxy size at fixed stellar mass from z~1.5 for cluster galaxies is less steep at more than 3{sigma}({prop.to}(1+z)-0.53+/-0.04) than the evolution of field galaxies ({prop.to}(1+z)-0.92+/-0.04). The difference in evolution is not measured when the median values of {gamma} are considered: {prop.to}(1+z)-0.84+/-0.04 in the field versus {prop.to}(1+z)-0.71+/-0.05 in clusters. In our sample, the tail of large galaxies is dominated by galaxies with 3x10^10^<M*/M_{sun}_<10^11^. At this low-mass end, the difference in the average size is better explained by the accretion of new galaxies that are quenched more efficiently in clusters and/or by different morphological mixing in the cluster and field environments. If part of the size evolution would be due to mergers, the difference that we see between cluster and field galaxies could be caused by higher merger rates in clusters at higher redshift, when galaxy velocities are lower.
- ID:
- ivo://CDS.VizieR/J/ApJ/566/945
- Title:
- Massive star forming regions at 1.2mm
- Short Name:
- J/ApJ/566/945
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a detailed 1.2mm continuum and CS spectral line study of a large sample of 69 massive star forming regions in very early stages of evolution, most of them prior to building up an ultracompact H II region.
376. MASSIVE Survey. VII.
- ID:
- ivo://CDS.VizieR/J/MNRAS/471/1428
- Title:
- MASSIVE Survey. VII.
- Short Name:
- J/MNRAS/471/1428
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We analyse the environmental properties of 370 local early-type galaxies (ETGs) in the MASSIVE and ATLAS^3D^ surveys, two complementary volume-limited integral-field spectroscopic (IFS) galaxy surveys spanning absolute K-band magnitude - 21.5>=M_K_>=-26.6, or stellar mass 8*10^9^<~M*<~2*10^12^M{sun}. We find these galaxies to reside in a diverse range of environments measured by four methods: group membership (whether a galaxy is a brightest group/cluster galaxy, satellite or isolated), halo mass, large-scale mass density (measured over a few Mpc) and local mass density (measured within the Nth neighbour). The spatially resolved IFS stellar kinematics provide robust measurements of the spin parameter {lambda}_e_ and enable us to examine the relationship among {lambda}_e_, M* and galaxy environment. We find a strong correlation between {lambda}_e_ and M*, where the average {lambda}_e_ decreases from ~0.4 to below 0.1 with increasing mass, and the fraction of slow rotators f_slow_ increase from ~10 to 90 per cent. We show for the first time that at fixed M*, there are almost no trends between galaxy spin and environment; the apparent kinematic morphology-density relation for ETGs is therefore primarily driven by M* and is accounted for by the joint correlations between M* and spin, and between M* and environment. A possible exception is that the increased f_slow_ at high local density is slightly more than expected based only on these joint correlations. Our results suggest that the physical processes responsible for building up the present-day stellar masses of massive galaxies are also very efficient at reducing their spin, in any environment.
- ID:
- ivo://CDS.VizieR/J/AJ/152/157
- Title:
- Mass models for 175 disk galaxies with SPARC
- Short Name:
- J/AJ/152/157
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We introduce SPARC (Spitzer Photometry and Accurate Rotation Curves): a sample of 175 nearby galaxies with new surface photometry at 3.6{mu}m and high-quality rotation curves from previous HI/H{alpha} studies. SPARC spans a broad range of morphologies (S0 to Irr), luminosities (~5dex), and surface brightnesses (~4dex). We derive [3.6] surface photometry and study structural relations of stellar and gas disks. We find that both the stellar mass-HI mass relation and the stellar radius-HI radius relation have significant intrinsic scatter, while the HI mass-radius relation is extremely tight. We build detailed mass models and quantify the ratio of baryonic to observed velocity (V_bar_/V_obs_) for different characteristic radii and values of the stellar mass-to-light ratio ({Upsilon}_*_) at [3.6]. Assuming {Upsilon}_*_{simeq}0.5M_{Sun}_/L_{Sun}_ (as suggested by stellar population models), we find that (i) the gas fraction linearly correlates with total luminosity; (ii) the transition from star-dominated to gas-dominated galaxies roughly corresponds to the transition from spiral galaxies to dwarf irregulars, in line with density wave theory; and (iii) V_bar_/V_obs_ varies with luminosity and surface brightness: high-mass, high-surface-brightness galaxies are nearly maximal, while low-mass, low-surface-brightness galaxies are submaximal. These basic properties are lost for low values of {Upsilon}_*_ {simeq}0.2M_{Sun}_/L_{Sun}_ as suggested by the DiskMass survey. The mean maximum-disk limit in bright galaxies is {Upsilon}_*_{simeq}0.7M_{Sun}_/L_{Sun}_ at [3.6]. The SPARC data are publicly available and represent an ideal test bed for models of galaxy formation.
- ID:
- ivo://CDS.VizieR/J/MNRAS/477/4187
- Title:
- Mass models of 171 galaxies
- Short Name:
- J/MNRAS/477/4187
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Mass models of a sample of 171 low- and high-surface brightness galaxies are presented in the context of the cold dark matter (CDM) theory using the NFW dark matter halo density distribution to extract a new concentration-viral mass relation (c-M_vir_). The rotation curves (RCs) are calculated from the total baryonic matter based on the 3.6{mu}m-band surface photometry, the observed distribution of neutral hydrogen, and the dark halo, in which the three adjustable parameters are the stellar mass-to-light ratio, halo concentration, and virial mass. Although accounting for a NFW dark halo profile can explain RC observations, the implied c-M_vir_ relation from RC analysis strongly disagrees with that resulting from different cosmological simulations. Also, the M/L-colour correlation of the studied galaxies is inconsistent with that expected from stellar population synthesis models with different stellar initial mass functions. Moreover, we show that the best-fitting stellar M/L ratios of 51 galaxies (30 per cent of our sample) have unphysically negative values in the framework of the {Lambda}CDM theory. This can be interpreted as a serious crisis for this theory. This suggests either that the commonly used NFW halo profile, which is a natural result of {Lambda}CDM cosmological structure formation, is not an appropriate profile for the dark haloes of galaxies, or, new dark matter physics or alternative gravity models are needed to explain the rotational velocities of disc galaxies.
- ID:
- ivo://CDS.VizieR/J/MNRAS/473/849
- Title:
- Mass segregation in Galactic stellar clusters
- Short Name:
- J/MNRAS/473/849
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We quantify the structure of a very large number of Galactic open clusters and look for evidence of mass segregation for the most massive stars in the clusters. We characterize the structure and mass segregation ratios of 1276 clusters in the Milky Way Stellar Cluster (MWSC) catalogue containing each at least 40 stars and that are located at a distance of up to ~2kpc from the Sun. We use an approach based on the calculation of the minimum spanning tree of the clusters, and for each one of them, we calculate the structure parameter Q and the mass segregation ratio {LAMBDA}_MSR_. Our findings indicate that most clusters possess a Q parameter that falls in the range 0.7-0.8 and are thus neither strongly concentrated nor do they show significant substructure. Only 27 per cent can be considered centrally concentrated with Q values >0.8. Of the 1276 clusters, only 14 per cent show indication of significant mass segregation ({LAMBDA}_MSR_>1.5). Furthermore, no correlation is found between the structure of the clusters or the degree of mass segregation with their position in the Galaxy. A comparison of the measured Q values for the young open clusters in the MWSC to N-body numerical simulations that follow the evolution of the Q parameter over the first 10Myr of the clusters life suggests that the young clusters found in the MWSC catalogue initially possessed local mean volume densities of {rho}*~=10-100M_{sun}_/pc^3^.
- ID:
- ivo://CDS.VizieR/J/other/BSAO/57.5
- Title:
- 2MASS-selected Flat Galaxy Catalog (2MFGC)
- Short Name:
- J/other/BSAO/57.
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- An all-sky catalog of 18020 disc-like galaxies is presented. The galaxies are selected from the Extended Source Catalog of the Two Micron All-Sky Survey (XSC 2MASS) basing on their 2MASS axial ratio a/b>=3. The Catalog contains data on magnitudes of a galaxy in the J, H, Ks bands, its axial ratio, positional angle, index of luminosity concentration, as well as identification of the galaxy with the LEDA and the NED databases. Unlike the available optical catalogs, the new 2MFGC catalog seems to be more suitable to study cosmic streaming on a scale of z~0.1. The dipole moment of distribution of the bright (K<11mag) 2MFGC objects (l=227{deg}, b=41{deg} or SGL=90{deg}, SGB=-43{deg}) lies within statistical errors (+/-15{deg}) in the direction of the IRAS dipole and the optical RFGC dipole.