According to the current cosmological paradigm, large scale structures form hierarchically in the Universe. Clusters of galaxies grow through a continuous accretion of mass. Nevertheless, the rate and manner of mass accretion events are still matters of debate. We have analysed the presence of substructures in one of the largest sample of nearby cluster galaxies available in the literature. We have determined the fraction of clusters with substructure and the properties of the galaxies located in such substructures. Substructure in the galaxy clusters was studied using the Dressler--Shectman test, which was calibrated through extensive Monte Carlo simulations of galaxy clusters similar to real ones. In order to avoid possible biases in the results due to differing incompleteness among clusters, we selected two galaxy populations: a) galaxies brighter than M$_{r} = $-20 located in clusters at $z < 0.1$ (EC1); and b) galaxies of brightness $M_{r} < -19$ located at $z<0.07$ (EC2). In the inner cluster regions ($r < r_{200}$) 11$\%$ and 33$\%$ of the clusters of EC1 and EC2 respectively show substructure. This fraction is larger in the outer cluster regions ($\approx 55\%$) for EC1 and EC2 samples. Cluster global properties, such as $σ_{c}$, $f_{b}$ or $Δm_{12}$ do not depend on the amount of cluster substructure. We have studied the properties of individual galaxies located in substructures in the EC1 and EC2 galaxy populations. The fraction of galaxies within substructures is larger in the outer cluster regions when fainter galaxies are included. The distribution of relative velocities of galaxies within substructures suggest that they consist of an infalling population mixed with backsplash galaxies. We can not rule out that the infalling galaxy population located in substructures are genuine field ones.
Anomalous flux ratios between quasar images are suspected to be caused by substructures in lens galaxies. We present new deep and high resolution H and Ks imaging of the strongly lensed quasar SDSS J0924+0219 obtained using the ESO VLT with adaptive optics and the Laser Guide Star system. SDSS J0924+0219 is particularly interesting as the observed flux ratio between the quasar images vastly disagree with the predictions from smooth mass models. With our adaptive optics observations we find a luminous object, Object L, located ~0.3" to the North of the lens galaxy, but we show that it can not b…
We search for the presence of substructure, a non-Gaussian, asymmetrical velocity distribution of galaxies, and large peculiar velocities of the main galaxies in galaxy clusters with at least 50 member galaxies, drawn from the SDSS DR8. We employ a number of 3D, 2D, and 1D tests to analyse the distribution of galaxies in clusters: 3D normal mixture modelling, the Dressler-Shectman test, the Anderson-Darling and Shapiro-Wilk tests and others. We find the peculiar velocities of the main galaxies, and use principal component analysis to characterise our results. More than 80% of the clusters in o…
With galaxy groups constructed from the Sloan Digital Sky Survey (SDSS), we analyze the expected galaxy-galaxy lensing signals around satellite galaxies residing in different host haloes and located at different halo-centric distances. We use Markov Chain Monte Carlo (MCMC) method to explore the potential constraints on the mass and density profile of subhaloes associated with satellite galaxies from SDSS-like surveys and surveys similar to the Large Synoptic Survey Telescope (LSST). Our results show that for SDSS-like surveys, we can only set a loose constraint on the mean mass of subhaloes. …
We extract a sample of disc stars within 200 pc of the Sun from the RAVE and SDSS surveys. Distances are estimated photometrically and proper motions are from ground-based data. We show that the velocity-space substructure first revealed in the Geneva-Copenhagen sample is also present in this completely independent sample. We also evaluate action-angle variables for these stars and show that the Hyades stream stars in these data are again characteristic of having been scattered at a Lindblad resonance. Unfortunately, analysis of such local samples can determine neither whether it is an inner o…
Gravitational lensing time delays are well known to depend on cosmological parameters, but they also depend on the details of the mass distribution of the lens. It is usual to model the mass distribution and use time-delay observations to infer cosmological parameters, but it is naturally also possible to take the cosmological parameters as given and use time delays as constraints on the mass distribution. This paper develops a method to isolate what exactly those constraints are, using a principal-components analysis of ensembles of free-form mass models. We find that time delays provide tigh…
We present an analysis of the substructure revealed by 407 RR Lyraes in Sloan Digital Sky Survey (SDSS) Stripe 82. Period estimates are determined to high accuracy using a string-length method. A subset of 178 RR Lyraes with spectrally derived metallicities are employed to derive metallicity-period-amplitude relations, which are then used to find metallicities and distances for the entire sample. The RR Lyraes lie between 5 and 115 kpc from the Galactic center. They are divided into subsets of 316 RRab types and 91 RRc types based on their period, colour and metallicity. The density distributi…
We use the SDSS-Gaia Catalogue to identify six new pieces of halo substructure. SDSS-Gaia is an astrometric catalogue that exploits SDSS data release 9 to provide first epoch photometry for objects in the Gaia source catalogue. We use a version of the catalogue containing $245\,316$ stars with all phase space coordinates within a heliocentric distance of $\sim 10$ kpc. We devise a method to assess the significance of halo substructures based on their clustering in velocity space. The two most substantial structures are multiple wraps of a stream which has undergone considerable phase mixing (S…
Using a high resolution radio image, we successfully resolve the two fold image components B and C of the quasar lens system SDSS J1029+2623. The flux anomalies associated with these two components in the optical regime persist, albeit less strongly, in our radio observations, suggesting that the cluster must be modeled by something more than a single central potential. We argue that placing substructure close to one of the components can account for a flux anomaly with negligible changes in the component positions. Our best fit model has a substructure mass of ~10^8 solar masses up to the mas…
We use the distribution of accreted stars in SDSS-Gaia DR2 to demonstrate that a non-trivial fraction of the dark matter halo within Galactocentric radii of 7.5-10 kpc and $|z| > 2.5$ kpc is in substructure, and thus may not be in equilibrium. Using a mixture likelihood analysis, we separate the contributions of an old, isotropic stellar halo and a younger anisotropic population. The latter dominates and is uniform within the region studied. It can be explained as the tidal debris of a disrupted massive satellite on a highly radial orbit, and is consistent with mounting evidence from recent st…
We present Hubble Space Telescope (HST) ACS and WFC3 observations of SDSS J1029+2623, a three-image quasar lens system produced by a foreground cluster at z=0.584. Our strong lensing analysis reveals 6 additional multiply imaged galaxies. We confirm the complex nature of the mass distribution of the lensing cluster, with a bimodal distribution which deviates from the Chandra X-ray SB distribution. The Einstein radius is estimated to be θ_E=15.2" \pm 0.5" for the quasar redshift of z=2.197. We derive a radial mass distribution from the combination of strong lensing, HST/ACS weak lensing, and Su…
Dynamical state of galaxy clusters is closely related to their observational properties in X-ray, optical and radio wavelengths. We develop a method to diagnose the substructure and dynamical state of galaxy clusters by using photometric data of Sloan Digital Sky Survey (SDSS). To trace mass distribution, the brightness distribution of member galaxies is smoothed by using a Gaussian kernel with a weight of their optical luminosities. After deriving the asymmetry, the ridge flatness and the normalized deviation of the smoothed optical map, we define a relaxation parameter, Gamma, to quantify dy…
The incidence of sub-galactic level substructures is an important quantity, as it is a generic prediction of high-resolution Cold Dark Matter (CDM) models which is susceptible to observational test. Confrontation of theory with observations is currently in an uncertain state. In particular, gravitational lens systems appear to show evidence for flux ratio anomalies, which are expected from CDM substructures although not necessarily in the same range of radius as observed. However, the current small samples of lenses suggest that the lens galaxies in these systems are unusually often accompanie…
We study the relations between the multimodality of galaxy clusters drawn from the SDSS DR8 and the environment where they reside. We find that multimodal clusters reside in higher density environment than unimodal clusters. We determine morphological types of superclusters and show that clusters in superclusters of spider morphology have higher probabilities to have substructure and larger peculiar velocities of their main galaxies than clusters in superclusters of filament morphology. Our study shows the importance of the role of superclusters as high density environment which affects the pr…
Using radio sources from the Faint Images of the Radio Sky at Twenty-cm (FIRST) survey, and optical counterparts in the Sloan Digital Sky Survey (SDSS), we have identified a large number of galaxy clusters. The radio sources within these clusters are driven by active galactic nuclei, and our cluster samples include clusters with bent, and straight, double-lobed radio sources. We also included a single-radio-component comparison sample. We examine these galaxy clusters for evidence of optical substructure, testing the possibility that bent double-lobed radio sources are formed as a result of la…
An optical photometric observation in 15 bands was carried out for nearby galaxy cluster Abell 1775 by the Beijing-Arizona-Taiwan-Connecticut (BATC) multi-color system. Over 5000 sources' spectral energy distributions (SEDs) were obtained. Since this cluster has also been observed by the Sloan Digital Sky Survey (SDSS), the BATC SEDs were combined with the SDSS five-band photometric data. Using the combined SEDs, 146 faint galaxies were selected as new member galaxies by the photometric redshift technique. Based on the positions, redshifts and 20-band SEDs of member galaxies, dynamical substru…
We construct a new sample of ~1700 solar neighbourhood halo subdwarfs from the Sloan Digital Sky Survey, selected using a reduced proper motion diagram. Radial velocities come from the SDSS spectra and proper motions from the light-motion curve catalogue of Bramich et al. (2008). Using a photometric parallax relation to estimate distances gives us the full phase-space coordinates. Typical velocity errors are in the range 30-50 km/s. This halo sample is one of the largest constructed to-date and the disc contamination is at a level of < 1 per cent. This enables us to calculate the halo velocity…
We use SDSS data to investigate the scaling relations of 127 NoSOCS and 56 CIRS galaxy clusters at low redshift ($z \le 0.10$). We show that richness and both optical and X-ray luminosities are reliable mass proxies. The scatter in mass at fixed observable is $\sim$ 40%, depending on the aperture, sample and observable considered. For example, for the massive CIRS systems $σ_{lnM500|N500}$ = 0.33 $\pm$ 0.05 and $σ_{lnM500|Lx}$ = 0.48 $\pm$ 0.06. For the full sample $σ_{lnM500|N500}$ = 0.43 $\pm$ 0.03 and $σ_{lnM500|Lx}$ = 0.56 $\pm$ 0.06. We estimate substructure using two and three dimensiona…
We study the relations between the multimodality of galaxy clusters drawn from the SDSS DR8 and the environment where they reside. As cluster environment we consider the global luminosity density field, supercluster membership, and supercluster morphology. We use 3D normal mixture modelling, the Dressler-Shectman test, and the peculiar velocity of cluster main galaxies as signatures of multimodality of clusters. We calculate the luminosity density field to study the environmental densities around clusters, and to find superclusters where clusters reside. We determine the morphology of superclu…
We study the distribution of line-of-sight velocities of galaxies in the vicinity of SDSS redMaPPer galaxy clusters. Based on their velocities, galaxies can be split into two categories: galaxies that are dynamically associated with the cluster, and random line-of-sight projections. Both the fraction of galaxies associated with the galaxy clusters, and the velocity dispersion of the same, exhibit a sharp feature as a function of radius. The feature occurs at a radial scale $R_{\rm edge} \approx 2.2R_{\rmλ}$, where $R_{\rmλ}$ is the cluster radius assigned by redMaPPer. We refer to $R_{\rm edge…
We obtain the projected mass distributions for two Subaru/Suprime-Cam fields in the southwest region (r\simlt 60') of the Coma cluster (z=0.0236) by weak lensing analysis and detect eight subclump candidates. We quantify the contribution of background large-scale structure (LSS) on the projected mass distributions using SDSS multi-bands and photometric data, under the assumption of mass-to-light ratio for field galaxies. We find that one of eight subclump candidates, which is not associated with any member galaxies, is significantly affected by LSS lensing. The mean projected mass for seven su…
We investigate the spatial distribution of chemical abundances in a sample of low metallicity Wolf-Rayet (WR) galaxies selected from the SDSS. We used the integral field spectroscopy technique in the optical spectral range (3700-6850 AA) with PMAS attached to the CAHA 3.5 m telescope. Our statistical analysis of the spatial distributions of O/H and N/O, as derived using the direct method or strong-line parameters consistent with it, indicates that metallicity is homogeneous in five out of the six analysed objects in scales of the order of several kpc. Only in the object WR404, a gradient of me…
We study the abundance of satellite galaxies as a function of primary stellar mass using the SDSS/DR7 spectroscopic catalogue. In contrast with previous studies, which focussed mainly on bright primaries, our central galaxies span a wide range of stellar mass, 10^7.5 < M_*^pri/M_sun < 10^11, from dwarfs to central cluster galaxies. Our analysis confirms that the average number of satellites around bright primaries, when expressed in terms of satellite-to-primary stellar mass ratio (m_*^sat/M_*^pri), is a strong function of M_*^pri. On the other hand, satellite abundance is largely independent …
We investigate the relationship between star formation (SF) and substructure in a sample of 107 nearby galaxy clusters using data from the Sloan Digital Sky Survey (SDSS). Several past studies of individual galaxy clusters have suggested that cluster mergers enhance cluster SF, while others find no such relationship. The SF fraction in multi-component clusters (0.228 +/- 0.007) is higher than that in single-component clusters (0.175 +/- 0.016) for galaxies with M^0.1_r < -20.5. In both single- and multi-component clusters, the fraction of star-forming galaxies increases with clustercentric dis…
We apply the iterative MCS deconvolution method (ISMCS) to near-IR HST archives data of seven gravitationally lensed quasars currently monitored by the COSMOGRAIL collaboration: HE 0047-1756, RX J1131-1231, SDSS J1138+0314, SDSS J1155+6346, SDSS J1226-0006, WFI J2026-4536 and HS 2209+1914. In doing so, we obtain relative positions for the lensed images and shape parameters for the light distribution of the lensing galaxy in each system. The lensed image positions are derived with 1-2 mas accuracy. To predict time delays and to test the ability of simple mass models to reproduce the observed co…
We present results from Chandra observations of the cluster lens SDSS J1029+2623 at z_l=0.58, which is a gravitationally lensed quasar with the largest known image separation. We clearly detect X-ray emission both from the lensing cluster and the three lensed quasar images. The cluster has an X-ray temperature of kT = 8.1 (+2.0, -1.2) keV and bolometric luminosity of L_X = 9.6e44 erg s^-1. Its surface brightness is centered near one of the brightest cluster galaxies, and it is elongated East-West. We identify a subpeak North-West of the main peak, which is suggestive of an ongoing merger. Even…
A clean measurement of the evolution of the galaxy cluster mass function can significantly improve our understanding of cosmology from the rapid growth of cluster masses below z < 0.5. Here we examine the consistency of cluster catalogues selected from the SDSS by applying two independent gravity-based methods using all available spectroscopic redshifts from the DR10 release. First, we detect a gravitational redshift related signal for 20,119 and 13,128 clusters with spectroscopic redshifts contained in the GMBCG and redMaPPer catalogues, respectively, at a level of $\sim - 10$ km s$^{-1}$. Th…
We analyse the kinematical and dynamical state of the galaxy cluster RXCJ1230.7+3439, at z=0.332, using 93 new spectroscopic redshifts of galaxies acquired at the 3.6m TNG telescope and from SDSS DR16 public data. We find that RXCJ1230 appears as a clearly isolated peak in the redshift space, with a global line-of-sight velocity dispersion of $1004_{-122}^{+147}$ km s$^{-1}$, and showing a very complex structure with the presence of three subclusters. Our analyses confirm that the three substructures detected are in a pre-merger phase, where the main interaction takes place with the south-west…
We report the detection of a dark substructure through direct gravitational imaging - undetected in the HST-ACS F814W image - in the gravitational lens galaxy of SLACS SDSSJ0946+1006 (the "Double Einstein Ring"). The detection is based on a Bayesian grid reconstruction of the two-dimensional surface density of the galaxy inside an annulus around its Einstein radius (few kpc). [...] We confirm this detection by modeling the system including a parametric mass model with a tidally truncated pseudo-Jaffe density profile; in that case the substructure mass is M_sub=(3.51+-0.15)x10^9 Msun, located a…
We study an SDSS sample of galaxies within 50 Mpc of the nominal center of the Ursa Major supercluster. Our aim is to study galaxy distribution around groups in the supercluster and the link between the distribution of relaxed and nonrelaxed galaxy systems with respect to the supercluster environment. Using the FoF algorithm, 40 galaxy groups were identified in this region. We classified the systems according to the results of normality and substructure tests applied to member galaxies. Then, we studied the relative distribution of relaxed and nonrelaxed systems across the supercluster. We fin…
We examine galaxy groups from the present epoch to z = 1 to explore the impact of group dynamics on galaxy evolution. We use group catalagues from the Sloan Digital Sky Survey (SDSS), the Group Environment and Evolution Collaboration (GEEC) and the high redshift GEEC2 sample to study how the observed member properties depend on galaxy stellar mass, group dynamical mass and dynamical state of the host group. We find a strong correlation between the fraction of non-star-forming (quiescent) galaxies and galaxy stellar mass, but do not detect a significant difference in the quiescent fraction with…
We provide new constraints on the connection between galaxies in the local universe, identified by the Sloan Digital Sky Survey (SDSS), and dark matter halos and their constituent substructures in the $Λ$CDM model using WMAP7 cosmological parameters. Predictions for the abundance and clustering properties of dark matter halos, and the relationship between dark matter hosts and substructures, are based on a high-resolution cosmological simulation, the Bolshoi simulation. We associate galaxies with halos and subhalos using subhalo abundance matching, performing a comprehensive analysis which inv…
The XMM Cluster Survey: Automating the estimation of hydrostatic mass for large samples of galaxy clusters I -- Methodology, Validation, & Application to the SDSSRM-XCS sample
The Milky Way's (MW) satellite population is a powerful probe of warm dark matter (WDM) models as the abundance of small substructures is very sensitive to the properties of the WDM particle. However, only a partial census of the MW's complement of satellite galaxies exists because surveys of the MW's close environs are incomplete both in depth and in sky coverage. We present a new Bayesian analysis that combines the sample of satellites recently discovered by the Dark Energy Survey (DES) with those found in the Sloan Digital Sky Survey (SDSS) to estimate the total satellite galaxy luminosity …
CFHT MegaCam Two Deep Fields Imaging Survey (2DFIS) II: Decoding the Lensing Profile of a "Rotating" Cluster with Deep CFHT Imaging
Shanghai Normal University（上海师范大学）；Shanghai Astronomical Observatory, Chinese Academy of Sciences（中国科学院上海天文台）；China Three Gorges University（三峡大学）；Hefei Institute of Technology（合肥工业大学）；University of Science and Technology of China（中国科学技术大学）；Purple Mountain Observatory, Chinese Academy of Sciences（中国科学院紫金山天文台）；Université Paris-Saclay（巴黎萨克雷大学）；Université Paris Cité（巴黎西岱大学）
本研究通过深度 CFHT 成像分析 RXCJ0110.+=1358 星系团，揭示光学双峰性源于丝状体投影，解决光学与 X 射线观测间的矛盾。
We compare the measured angular cross-correlation between the Fermi-LAT gamma-ray sky and catalogues of extra-galactic objects with the expected signal induced by weakly interacting massive particle (WIMP) dark matter (DM). We include a detailed description of the contribution of astrophysical gamma-ray emitters such as blazars, misaligned AGN and star forming galaxies, and perform a global fit to the measured cross-correlation. Five catalogues are considered: SDSS-DR6 quasars, 2MASS galaxies, NVSS radio galaxies, SDSS-DR8 Luminous Red Galaxies and SDSS-DR8 main galaxy sample. To model the cro…
We study the possible rotation of cluster galaxies, developing, testing and applying a novel algorithm which identifies rotation, if such does exist, as well as its rotational centre, its axis orientation, rotational velocity amplitude and, finally, the clockwise or counterclockwise direction of rotation on the plane of the sky. To validate our algorithms we construct realistic Monte Carlo mock rotating clusters and confirm that our method provides robust indications of rotation. We then apply our methodology on a sample of Abell clusters with z<~0.1 with member galaxies selected from the Sloa…
We present ultraviolet (UV) color-magnitude relations (CMRs) of early-type dwarf galaxies in the Virgo cluster, based on Galaxy Evolution Explorer (GALEX) UV and Sloan Digital Sky Survey (SDSS) optical imaging data. We find that dwarf lenticular galaxies (dS0s), including peculiar dwarf elliptical galaxies (dEs) with disk substructures and blue centers, show a surprisingly distinct and tight locus separated from that of ordinary dEs, which is not clearly seen in previous CMRs. The dS0s in UV CMRs follow a steeper sequence than dEs and show bluer UV-optical color at a given magnitude. We also f…
Modern cosmological simulations model the universe with increasing sophistication and at higher spatial and temporal resolutions. These enhancements permit detailed comparisons between the simulation outputs and real observational data. Recent projects such as Illustris are capable of producing simulated images that are comparable to those obtained from local surveys. This paper tests how well Illustris achieves this goal across a diverse population of galaxies using visual morphologies derived from Galaxy Zoo citizen scientists. Morphological classifications provided by volunteers for simulat…
Environmental effects have an important influence on cluster galaxies, but studies at very faint magnitudes (R>21) are almost exclusively based on imaging. We present here a very deep spectroscopic survey of galaxies on the line of sight to Coma, based on redshifts obtained with VLT/VIMOS for 715 galaxies in the unprecedented magnitude range 21<R<23 (absolute magnitude -14 to -12). We confirm the substructures previously identified in Coma by Adami et al. (2005a), and identify three new ones. We detect many groups behind Coma: a large structure at z~0.5, the SDSS Great Wall, and a large and ve…
We present the photometric and kinematic characterization of two groups, USGC U268 and USGC U376 located in different regions of the Leo cloud. U268, composed of 10 catalogued members and 11 new added members, has a small fraction (~24%) of early-type galaxies (ETGs). U376 has 16 plus 8 new added members, with ~38% of ETGs. We find the presence of significant substructures in both groups suggesting that they are likely accreting galaxies. U268 is located in a more loose environment than U376. For each member galaxy, broad band integrated and surface photometry have been obtained in far-UV and …
We study the formation and evolution of filamentary configurations of dark matter haloes in voids. Our investigation uses the high-resolution LambdaCDM simulation CosmoGrid to look for void systems resembling the VGS_31 elongated system of three interacting galaxies that was recently discovered by the Void Galaxy Survey (VGS) inside a large void in the SDSS galaxy redshift survey. HI data revealed these galaxies to be embedded in a common elongated envelope, possibly embedded in intravoid filament. In the CosmoGrid simulation we look for systems similar to VGS_31 in mass, size and environment.…
We have combined the semi-analytic galaxy formation model of Guo et al. (2011) with the particle-tagging technique of Cooper et al. (2010) to predict galaxy surface brightness profiles in a representative sample of ~1900 massive dark matter haloes (10^12--10^14 M_sol) from the Millennium II Lambda-CDM N-body simulation. Here we present our method and basic results focusing on the outer regions of galaxies, consisting of stars accreted in mergers. These simulations cover scales from the stellar haloes of Milky Way-like galaxies to the 'cD envelopes' of groups and clusters, and resolve low surfa…
We study a sample of 19 galaxy clusters in the redshift range $0.15<z<0.30$ with highly complete spectroscopic membership catalogues (to $K < K^{\ast}(\rm z)+1.5$) from the Arizona Cluster Redshift Survey (ACReS); individual weak-lensing masses and near-infrared data from the Local Cluster Substructure Survey (LoCuSS); and optical photometry from the Sloan Digital Sky Survey (SDSS). We fit the scaling relations between total cluster luminosity in each of six bandpasses (${\it grizJK}$) and cluster mass, finding cluster luminosity to be a promising mass proxy with low intrinsic scatter $σ_{\ln …
We demonstrate how the total luminosity in satellite galaxies is a powerful probe of dark matter halos around central galaxies. The method cross-correlates central galaxies in spectroscopic galaxy samples with fainter galaxies detected in photometric surveys. After background subtraction, the excess galaxies around the central galaxies represent faint satellite galaxies within the dark matter halo. Using abundance matching models, we show that the the total galaxy luminosity, L_sat, scales linearly with host halo mass, making L_sat an excellent proxy for M_h. L_sat is also sensitive to the for…
The fine details of the large-scale structure in the local universe provide important empirical benchmarks for testing cosmological models of structure formation. Dwarf galaxies are key object for such studies. Enlarge the sample of known dwarf galaxies in the local universe. We performed a search for faint, unresolved low-surface brightness dwarf galaxies in the M101 group complex, including the region around the major spiral galaxies M101, M51, and M63 lying at a distance 7.0, 8.6, and 9.0 Mpc, respectively. The new dwarf galaxy sample can be used in a first step to test for significant subs…
The stellar mass assembly of brightest cluster galaxies (BCGs) is still debated. We have observed in CO with the IRAM-30m two star forming BCGs belonging to SpARCS clusters, 3C 244.1 ($z=0.4$) and SDSS J161112.65+550823.5 ($z=0.9$), and compared their molecular gas and star formation properties with those of a compilation of $\sim100$ distant cluster galaxies, including nine additional distant BCGs at ${z\sim0.4-3.5}$. We have set robust upper limits of $M_{{\rm H}_2}<1.0\times10^{10}~M_\odot$ and $<2.8\times10^{10}~M_\odot$ to their molecular gas content, respectively, as well as to the molec…
