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Gillian Wilson

Publications and source records attributed to Gillian Wilson.

At least 55 records · Page 3Linked to original sources
arXiv2022

MAGAZ3NE: High Stellar Velocity Dispersions for Ultra-Massive Quiescent Galaxies at $z\gtrsim3$

In this work we publish stellar velocity dispersions, sizes, and dynamical masses for 8 ultra-massive galaxies (UMGs; log($M$/M$_\odot>11$, $z\gtrsim3$) from the Massive Ancient Galaxies At $z>3$ NEar-infrared (MAGAZ3NE) Survey, more than doubling the number of such galaxies with velocity dispersion measurements at this epoch. Using the deep Keck/MOSFIRE and Keck/NIRES spectroscopy of these objects in the $H$- and $K$-bandpasses, we obtain large velocity dispersions of $\sim400$ km s$^{-1}$ for most of the objects, which are some of the highest stellar velocity dispersions measured, and $\sim40$\% larger than those measured for galaxies of similar mass at $z\sim1.7$. The sizes of these objects are also smaller by a factor of 1.5-3 compared to this same $z\sim1.7$ sample. We combine these large velocity dispersions and small sizes to obtain dynamical masses. The dynamical masses are similar to the stellar masses of these galaxies, consistent with a Chabrier initial mass function (IMF). Considered alongside previous studies of massive quiescent galaxies across $0.2<z<4.0$, there is evidence for an evolution in the relation between the dynamical mass - stellar mass ratio and velocity dispersion as a function of redshift. This implies an IMF with fewer low mass stars (e.g., Chabrier IMF) for massive quiescent galaxies at higher redshifts in conflict with the bottom-heavy IMF (e.g., Salpeter IMF) found in their likely $z\sim0$ descendants, though a number of alternative explanations such as a different dynamical structure or significant rotation are not ruled out. Similar to data at lower redshifts, we see evidence for an increase of IMF normalization with velocity dispersion, though the $z\gtrsim3$ trend is steeper than that for $z\sim0.2$ early-type galaxies and offset to lower dynamical-to-stellar mass ratios.

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arXiv2022

The GOGREEN Survey: Constraining the Satellite Quenching Timescale in Massive Clusters at $\boldsymbol{z} \gtrsim 1$

We model satellite quenching at $z \sim 1$ by combining $14$ massive ($10^{13.8} < M_{\mathrm{halo}}/\mathrm{M}_{\odot} < 10^{15}$) clusters at $0.8 < z < 1.3$ from the GOGREEN and GCLASS surveys with accretion histories of $56$ redshift-matched analogs from the IllustrisTNG simulation. Our fiducial model, which is parameterized by the satellite quenching timescale ($τ_{\rm quench}$), accounts for quenching in our simulated satellite population both at the time of infall by using the observed coeval field quenched fraction and after infall by tuning $τ_{\rm quench}$ to reproduce the observed satellite quenched fraction versus stellar mass trend. This model successfully reproduces the observed satellite quenched fraction as a function of stellar mass (by construction), projected cluster-centric radius, and redshift and is consistent with the observed field and cluster stellar mass functions at $z \sim 1$. We find that the satellite quenching timescale is mass dependent, in conflict with some previous studies at low and intermediate redshift. Over the stellar mass range probed ($M_{\star}> 10^{10}~\mathrm{M}_{\odot}$), we find that the satellite quenching timescale decreases with increasing satellite stellar mass from $\sim1.6~{\rm Gyr}$ at $10^{10}~\mathrm{M}_{\odot}$ to $\sim 0.6 - 1~{\rm Gyr}$ at $10^{11}~\mathrm{M}_{\odot}$ and is roughly consistent with the total cold gas (H{\scriptsize I}+H$_{2}$) depletion timescales at intermediate $z$, suggesting that starvation may be the dominant driver of environmental quenching at $z < 2$. Finally, while environmental mechanisms are relatively efficient at quenching massive satellites, we find that the majority ($\sim65-80\%$) of ultra-massive satellites ($M_{\star} > 10^{11}~\mathrm{M}_{\odot}$) are quenched prior to infall.

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arXiv2022

An Assessment of the In-Situ Growth of the Intracluster Light in the High Redshift Galaxy Cluster SpARCS1049+56

The formation of the stellar mass within galaxy cluster cores is a poorly understood process. It features the complicated physics of cooling flows, AGN feedback, star formation and more. Here, we study the growth of the stellar mass in the vicinity of the Brightest Cluster Galaxy (BCG) in a z = 1.7 cluster, SpARCS1049+56. We synthesize a reanalysis of existing HST imaging, a previously published measurement of the star formation rate, and the results of new radio molecular gas spectroscopy. These analyses represent the past, present and future star formation respectively within this system. We show that a large amount of stellar mass -- between $(2.2 \pm 0.5) \times 10^{10} \: M_\odot$ and $(6.6 \pm 1.2) \times 10^{10}\: M_\odot$ depending on the data processing -- exists in a long and clumpy tail-like structure that lies roughly 12 kpc off the BCG. Spatially coincident with this stellar mass is a similarly massive reservoir ($(1.0 \pm 0.7) \times 10^{11} \: M_\odot$) of molecular gas that we suggest is the fuel for the immense star formation rate of $860 \pm 130 \: M_\odot$/yr, as measured by infrared observations. Hlavacek-Larrondo et al. 2021 surmised that massive, runaway cooling of the hot intracluster X-ray gas was feeding this star formation, a process that had not been observed before at high-redshift. We conclude, based on the amount of fuel and current stars, that this event may be rare in the lifetime of a cluster, producing roughly 15 to 21% of the Intracluster Light (ICL) mass in one go, though perhaps a common event for all galaxy clusters.

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arXiv2021

Spectroscopic Confirmation of a Protocluster at $z=3.37$ with a High Fraction of Quiescent Galaxies

We report the discovery of MAGAZ3NE J095924+022537, a spectroscopically-confirmed protocluster at $z = 3.3665^{+0.0009}_{-0.0012}$ around a spectroscopically-confirmed $UVJ$-quiescent ultra-massive galaxy (UMG; $M_{\star}=2.34^{+0.23}_{-0.34}\times10^{11} {\rm M}_\odot$) in the COSMOS UltraVISTA field. We present a total of 38 protocluster members (14 spectroscopic and 24 photometric), including the UMG. Notably, and in marked contrast to protoclusters previously reported at this epoch which have been found to contain predominantly star-forming members, we measure an elevated fraction of quiescent galaxies relative to the coeval field ($73.3^{+26.7}_{-16.9}\%$ versus $11.6^{+7.1}_{-4.9}\%$ for galaxies with stellar mass $M_{\star} \geq 10^{11} {\rm M}_\odot$). This high quenched fraction provides a striking and important counterexample to the seeming ubiquitousness of star-forming galaxies in protoclusters at $z>2$ and suggests, rather, that protoclusters exist in a diversity of evolutionary states in the early Universe. We discuss the possibility that we might be observing either "early mass quenching" or non-classical "environmental quenching." We also present the discovery of MAGAZ3NE J100028+023349, a second spectroscopically-confirmed protocluster, at a very similar redshift of $z = 3.3801^{+0.0213}_{-0.0281}$. We present a total of 20 protocluster members, 12 of which are photometric and 8 spectroscopic including a post-starburst UMG ($M_{\star}=2.95^{+0.21}_{-0.20}\times10^{11} {\rm M}_\odot$). Protoclusters MAGAZ3NE J0959 and MAGAZ3NE J1000 are separated by 18 arcminutes on the sky (35 comoving Mpc), in good agreement with predictions from simulations for the size of "Coma"-type cluster progenitors at this epoch. It is highly likely that the two UMGs are the progenitors of Brightest Cluster Galaxies (BCGs) seen in massive virialized clusters at lower redshift.

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arXiv2021

HST/WFC3 grism observations of $z\sim1$ clusters: Evidence for rapid outside-in environmental quenching from spatially resolved H$α$ maps

We present and publicly release (https://www.gclasshst.com) the first spatially resolved H$α$ maps of star-forming cluster galaxies at $z\sim1$, made possible with the Wide Field Camera 3 (WFC3) G141 grism on the Hubble Space Telescope (HST). Using a similar but updated method to 3D-HST in the field environment, we stack the H$α$ maps in bins of stellar mass, measure the half-light radius of the H$α$ distribution and compare it to the stellar continuum. The ratio of the H$α$ to stellar continuum half-light radius, $R[\mathrm{H}α/\mathrm{C}]=\frac{R_{\mathrm{eff, H}α}}{R_{\mathrm{eff, Cont}}}$, is smaller in the clusters by $(6\pm9)\%$, but statistically consistent within $1σ$ uncertainties. A negligible difference in $R[\mathrm{H}α/\mathrm{C}]$ with environment is surprising, given the higher quenched fractions in the clusters relative to the field. We postulate that the combination of high quenched fractions and no change in $R[\mathrm{H}α/\mathrm{C}]$ with environment can be reconciled if environmental quenching proceeds rapidly. We investigate this hypothesis by performing similar analysis on the spectroscopically-confirmed recently quenched cluster galaxies. 87% have H$α$ detections, with star formation rates $8\pm1$ times lower than star-forming cluster galaxies of similar stellar mass. Importantly, these galaxies have a $R[\mathrm{H}α/\mathrm{C}]$ that is $(81\pm8)\%$ smaller than coeval star-forming field galaxies at fixed stellar mass. This suggests the environmental quenching process occurred outside-in. We conclude that disk truncation due to ram-pressure stripping is occurring in cluster galaxies at $z\sim1$, but more rapidly and/or efficiently than in $z\lesssim0.5$ clusters, such that the effects on $R[\mathrm{H}α/\mathrm{C}]$ become observable just after the cluster galaxy has recently quenched.

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arXiv2021

The GOGREEN survey: Transition Galaxies and The Evolution of Environmental Quenching

We measure the rate of environmentally-driven star formation quenching in galaxies at $z\sim 1$, using eleven massive ($M\approx 2\times10^{14}\,\mathrm{M}_\odot$) galaxy clusters spanning a redshift range $1.0 10.5$) we do not find any significant excess of transition galaxies in clusters, relative to a comparison field sample at the same redshift. It is likely that such galaxies were quenched prior to their accretion in the cluster, in group, filament or protocluster environments. For lower stellar mass galaxies ($9.5<\log{M/\mathrm{M}_\odot}<10.5$) there is a small but significant excess of transition galaxies in clusters, accounting for an additional $\sim 5-10$ per cent of the population compared with the field. We show that our data are consistent with a scenario in which 20--30 per cent of low-mass, star-forming galaxies in clusters are environmentally quenched every Gyr, and that this rate slowly declines from $z=1$ to $z=0$. While environmental quenching of these galaxies may include a long delay time during which star formation declines slowly, in most cases this must end with a rapid ($τ<1$ Gyr) decline in star formation rate.

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arXiv2021

The GOGREEN Survey: Evidence of an excess of quiescent disks in clusters at $1.0<z<1.4$

We present results on the measured shapes of 832 galaxies in 11 galaxy clusters at 1.0 < z <1.4 from the GOGREEN survey. We measure the axis ratio ($q$), the ratio of the minor to the major axis, of the cluster galaxies from near-infrared Hubble Space Telescope imaging using Sérsic profile fitting and compare them with a field sample. We find that the median $q$ of both star-forming and quiescent galaxies in clusters increases with stellar mass, similar to the field. Comparing the axis ratio distributions between clusters and the field in four mass bins, the distributions for star-forming galaxies in clusters are consistent with those in the field. Conversely, the distributions for quiescent galaxies in the two environments are distinct, most remarkably in $10.1\leq\log(M/{\rm M}_{\odot})<10.5$ where clusters show a flatter distribution, with an excess at low $q$. Modelling the distribution with oblate and triaxial components, we find that the cluster and field sample difference is consistent with an excess of flattened oblate quiescent galaxies in clusters. The oblate population contribution drops at high masses, resulting in a narrower $q$ distribution in the massive population than at lower masses. Using a simple accretion model, we show that the observed $q$ distributions and quenched fractions are consistent with a scenario where no morphological transformation occurs for the environmentally quenched population in the two intermediate mass bins. Our results suggest that environmental quenching mechanism(s) likely produce a population that has a different morphological mix than those resulting from the dominant quenching mechanism in the field.

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arXiv2021

The HST See Change Program: I. Survey Design, Pipeline, and Supernova Discoveries

The See Change survey was designed to make $z>1$ cosmological measurements by efficiently discovering high-redshift Type Ia supernovae (SNe Ia) and improving cluster mass measurements through weak lensing. This survey observed twelve galaxy clusters with the Hubble Space Telescope spanning the redshift range $z=1.13$ to $1.75$, discovering 57 likely transients and 27 likely SNe Ia at $z\sim 0.8-2.3$. As in similar previous surveys (Dawson et al. 2009), this proved to be a highly efficient use of HST for SN observations; the See Change survey additionally tested the feasibility of maintaining, or further increasing, the efficiency at yet higher redshifts, where we have less detailed information on the expected cluster masses and star-formation rates. We find that the resulting number of SNe Ia per orbit is a factor of $\sim 8$ higher than for a field search, and 45% of our orbits contained an active SN Ia within 22 rest-frame days of peak, with one of the clusters by itself yielding 6 of the SNe Ia. We present the survey design, pipeline, and SN discoveries. Novel features include fully blinded SN searches, the first random forest candidate classifier for undersampled IR data (with a 50% detection threshold within 0.05 magnitudes of human searchers), real-time forward-modeling photometry of candidates, and semi-automated photometric classifications and follow-up forecasts. We also describe the spectroscopic follow-up, instrumental in measuring host-galaxy redshifts. The cosmology analysis of our sample will be presented in a companion paper.

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arXiv2021

A CO Survey of SpARCS Star-Forming Brightest Cluster Galaxies: Evidence for Uniformity in BCG Molecular Gas Processing Across Cosmic Time

We present ALMA CO (2-1) detections of 24 star-forming Brightest Cluster Galaxies (BCGs) over $0.2<z<1.2$, constituting the largest and most distant sample of molecular gas measurements in BCGs to date. The BCGs are selected from the Spitzer Adaptation of the Red-Sequence Cluster Survey (SpARCS) to be IR-bright and therefore star-forming. We find that molecular gas is common in star-forming BCGs, detecting CO at a detection rate of 80% in our target sample of 30 objects. We additionally provide measurements of the star formation rate (SFR) and stellar mass, calculated from existing MIPS 24 $μ$m and IRAC 3.6 $μ$m fluxes, respectively. We find these galaxies have molecular gas masses of $0.7-11.0\times 10^{10}\ \mathrm{M}_\odot$, comparable to other BCGs in this redshift range, and specific star formation rates which trace the Elbaz et al. (2011) Main Sequence. We compare our BCGs to those of the lower-redshift, cooling-flow BCG sample assembled by Edge (2001) and find that at z $\lesssim 0.6$ the two samples show very similar correlations between their gas masses and specific SFRs. We suggest that, in this redshift regime, the $\sim10\%$ (Webb et al., 2015) of BCGs that are star-forming process any accreted molecular gas into stars through means that are agnostic to both their redshift and their cluster mass.

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arXiv2020

The Rapid Build-up of Massive Early-type Galaxies. Supersolar Metallicity, High Velocity Dispersion and Young Age for an ETG at z=3.35

Thanks to very deep spectroscopic observations carried out at the Large Binocular Telescope, we measured simultaneously stellar age, metallicity and velocity dispersion for C1-23152, an ETG at redshift $z$=3.352, corresponding to an epoch when the Universe was $\sim$1.8 Gyr old. The analysis of its spectrum shows that this galaxy, hosting an AGN, formed and assembled $\sim$2$\times$10$^{11}$ M$_\odot$ shaping its morphology within the $\sim$600 Myr preceding the observations, since $z$$\sim$4.6. The stellar population has a mean mass-weighted age 400$^{+30}_{-70}$ Myr and it is formed between $\sim$600 Myr and $\sim$150 Myr before the observed epoch, this latter being the time since quenching. Its high stellar velocity dispersion, $σ_e$=409$\pm$60 km s$^{-1}$, confirms the high mass (M$_{dyn}$=$2.2(\pm0.4)$$\times$10$^{11}$ M$_\odot$) and the high mass density ($Σ_e^{M^*}$=$Σ_{1kpc}=3.2(\pm0.7)\times10^{10}$ M$_\odot$ kpc$^{-2}$), suggesting a fast dissipative process at its origin. The analysis points toward a supersolar metallicity, [Z/H]=0.25$^{+0.006}_{-0.10}$, in agreement with the above picture, suggesting a star formation efficiency much higher than the replenishment time. However, sub-solar metallicity values cannot be firmly ruled out by our analysis. Quenching must have been extremely efficient to reduce the star formation to SFR$<$6.5 M$_\odot$ yr$^{-1}$ in less than 150 Myr. This could be explained by the presence of the AGN, even if a causal relation cannot be established from the data. C1-23152 has the same stellar and physical properties of the densest ETGs in the local Universe of comparable mass, suggesting that they are C1-23152-like galaxies which evolved to $z=0$ unperturbed.

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arXiv2020

The Number Densities and Stellar Populations of Massive Galaxies at 3 < z < 6: A Diverse, Rapidly Forming Population in the Early Universe

We present the census of massive (log(M$_{*}$/M$_{\odot}$)$\geq 11$) galaxies at $3 3$. The significant increase in observed number densities at $z\sim4$ ($>\times$ 5 in $\lesssim600$ Myrs) implies that this is the epoch at which log(M$_{*}$/M$_{\odot}$)$\geq 11$ galaxies emerge in significant numbers, with stellar ages ($\approx500-900$ Myrs) indicating rapid formation epochs as early as $z\sim7$. Leveraging ancillary multi-wavelength datasets, we perform panchromatic SED modelling to constrain the total star-formation activity of the sample. The star-formation activity of the sample is generally consistent with being on the star-formation main sequence at the considered redshifts, with $\approx15-25\%$ of the population showing evidence of suppressed star-formation rates, indicating that quenching mechanisms are already at play by $z\sim4$. We stack available HST imaging, confirming their compact nature ($r_{e}\lesssim2.2$ kpc), consistent with expected sizes of high-$z$ star-forming galaxies. Finally, we discuss how our results are in-line with the early formation epochs and short formation timescales inferred from the fossil records of the most massive galaxies in the Universe.

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arXiv2020

The GOGREEN and GCLASS Surveys: First Data Release

We present the first public data release of the GOGREEN and GCLASS surveys of galaxies in dense environments, spanning a redshift range $0.8<z<1.5$. The surveys consist of deep, multiwavelength photometry and extensive Gemini GMOS spectroscopy of galaxies in 26 overdense systems ranging in halo mass from small groups to the most massive clusters. The objective of both projects was primarily to understand how the evolution of galaxies is affected by their environment, and to determine the physical processes that lead to the quenching of star formation. There was an emphasis on obtaining unbiased spectroscopy over a wide stellar mass range ($M\gtrsim 2\times 10^{10}~\mathrm{M}_\odot$), throughout and beyond the cluster virialized regions. The final spectroscopic sample includes 2771 unique objects, of which 2257 have reliable spectroscopic redshifts. Of these, 1704 have redshifts in the range $0.8<z<1.5$, and nearly 800 are confirmed cluster members. Imaging spans the full optical and near-infrared wavelength range, at depths comparable to the UltraVISTA survey, and includes \textit{HST}/WFC3 F160W (GOGREEN) and F140W (GCLASS). This data release includes fully reduced images and spectra, with catalogues of advanced data products including redshifts, line strengths, star formation rates, stellar masses and rest-frame colours. Here we present an overview of the data, including an analysis of the spectroscopic completeness and redshift quality.

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arXiv2020

The GOGREEN survey: The environmental dependence of the star-forming galaxy main sequence at $1.0<z<1.5$

We present results on the environmental dependence of the star-forming galaxy main sequence in 11 galaxy cluster fields at $1.0 < z < 1.5$ from the Gemini Observations of Galaxies in Rich Early Environments Survey (GOGREEN) survey. We use a homogeneously selected sample of field and cluster galaxies whose membership is derived from dynamical analysis. Using [OII]-derived star formation rates (SFRs), we find that cluster galaxies have suppressed SFRs at fixed stellar mass in comparison to their field counterparts by a factor of 1.4 $\pm$ 0.1 ($\sim3.3σ$) across the stellar mass range: $9.0 < \log(M_{*} /M_{\odot}) < 11.2$. We also find that this modest suppression in the cluster galaxy star-forming main sequence is mass and redshift dependent: the difference between cluster and field increases towards lower stellar masses and lower redshift. When comparing the distribution of cluster and field galaxy SFRs to the star-forming main sequence, we find an overall shift towards lower SFRs in the cluster population, and note the absence of a tail of high SFR galaxies as seen in the field. Given this observed suppression in the cluster galaxy star-forming main sequence, we explore the implications for several scenarios such as formation time differences between cluster and field galaxies, and environmentally-induced star formation quenching and associated timescales.

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arXiv2020

The H$α$ star formation main sequence in cluster and field galaxies at $z\sim1.6$

We calculate H$α$-based star formation rates and determine the star formation rate-stellar mass relation for members of three SpARCS clusters at $z \sim 1.6$ and serendipitously identified field galaxies at similar redshifts to the clusters. We find similar star formation rates in cluster and field galaxies throughout our range of stellar masses. The results are comparable to those seen in other clusters at similar redshifts, and consistent with our previous photometric evidence for little quenching activity in clusters. One possible explanation for our results is that galaxies in our $z \sim 1.6$ clusters have been accreted too recently to show signs of environmental quenching. It is also possible that the clusters are not yet dynamically mature enough to produce important environmental quenching effects shown to be important at low redshift, such as ram pressure stripping or harassment.

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arXiv2020

The Massive Ancient Galaxies At $z>3$ NEar-infrared (MAGAZ3NE) Survey: Confirmation of Extremely Rapid Star-Formation and Quenching Timescales for Massive Galaxies in the Early Universe

We present near-infrared spectroscopic confirmations of a sample of 16 photometrically-selected galaxies with stellar masses log(M_star/M_sun) > 11 at redshift z > 3 from the XMM-VIDEO and COSMOS-UltraVISTA fields using Keck/MOSFIRE as part of the MAGAZ3NE survey. Eight of the ultra-massive galaxies (UMGs) have specific star formation rates (sSFR) < 0.03 Gyr-1, with negligible emission lines. Another seven UMGs show emission lines consistent with active galactic nuclei and/or star formation, while only one UMG has sSFR > 1 Gyr-1. Model star formation histories of these galaxies describe systems that formed the majority of their stars in vigorous bursts of several hundred Myr duration around 4 < z < 6during which hundreds to thousands of solar masses were formed per year. These formation ages of < 1 Gyr prior to observation are consistent with ages derived from measurements of Dn(4000) and EW0(Hδ). Rapid quenching followed these bursty star-forming periods, generally occurring less than 350 Myr before observation, resulting in post-starburst SEDs and spectra for half the sample. The rapid formation timescales are consistent with the extreme star formation rates observed in 4 < z < 7 dusty starbursts observed with ALMA, suggesting that such dusty galaxies are progenitors of these UMGs. While such formation histories have been suggested in previous studies, the large sample introduced here presents the most compelling evidence yet that vigorous star formation followed by rapid quenching is almost certainly the norm for high mass galaxies in the early universe. The UMGs presented here were selected to be brighter than Ks = 21.7 raising the intriguing possibility that even (fainter) older quiescent UMGs could exist at this epoch.

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arXiv2020

Cosmological Constraint on $Ω_m$ and $σ_8$ from Cluster Abundances using the $\mathtt{GalWCat19}$ Optical-Spectroscopic SDSS Catalog

We derive cosmological constraints on the matter density, \om, and the amplitude of fluctuations, \sig, using $\mathtt{GalWCat19}$, a catalog of 1800 galaxy clusters we identified in the Sloan Digital Sky Survey-DR13 spectroscopic data set using our GalWeight technique to determine cluster membership \citep{Abdullah18,Abdullah19}. By analyzing a subsample of 756 clusters in a redshift range of $0.045\leq z \leq 0.125$ and virial masses of $M\geq 0.8\times10^{14}$ \hm ~with mean redshift of $z = 0.085$, we obtain \om ~$=0.310^{+0.023}_{-0.027} \pm 0.041$ (systematic) and \sig ~$=0.810^{+0.031}_{-0.036}\pm 0.035$ (systematic), with a cluster normalization relation of $σ_8= 0.43 Ω_m^{-0.55}$. There are several unique aspects to our approach: we use the largest spectroscopic data set currently available, and we assign membership using the GalWeight technique which we have shown to be very effective at simultaneously maximizing the number of {\it{bona fide}} cluster members while minimizing the number of contaminating interlopers. Moreover, rather than employing scaling relations, we calculate cluster masses individually using the virial mass estimator. Since $\mathtt{GalWCat19}$ is a low-redshift cluster catalog we do not need to make any assumptions about evolution either in cosmological parameters or in the properties of the clusters themselves. Our constraints on \om ~and \sig ~are consistent and very competitive with those obtained from non-cluster abundance cosmological probes such as Cosmic Microwave Background (CMB), Baryonic Acoustic Oscillation (BAO), and supernovae (SNe). The joint analysis of our cluster data with Planck18+BAO+Pantheon gives \om ~$=0.315^{+0.013}_{-0.011}$ and \sig ~$=0.810^{+0.011}_{-0.010}$.

astro-ph.CO↗