LoCuSS: first results from strong-lensing analysis of 20 massive galaxy clusters at z= 0.2

By J. Richard, Graham P. Smith, Jean-Paul Kneib, Richard S. Ellis, A. Sanderson, L. Pei, Thomas Targett, D. Sand, M. Swinbank, H. Dannerbauer and 6 more. 2009

148 citations recorded by the source corpus.

We present a statistical analysis of a sample of 20 strong lensing clusters drawn from the Local Cluster Substructure Survey, based on high-resolution Hubble Space Telescope imaging of the cluster cores and follow-up spectroscopic observations using the Keck-I telescope. We use detailed parametrized models of the mass distribution in the cluster cores, to measure the total cluster mass and fraction of that mass associated with substructures within R ≤ 250 kpc. These measurements are compared with the distribution of baryons in the cores, as traced by the old stellar populations and the X-ray emitting intracluster medium. Our main results include: (i) the distribution of Einstein radii is lognormal, with a peak and 1σ width of〈log_(10)θ_E(z=2)〉= 1.16 ± 0.28; (ii) we detect an X-ray/lensing mass discrepancy of〈M_(SL)/M_X〉= 1.3 at 3σ significance – clusters with larger substructure fractions displaying greater mass discrepancies, and thus greater departures from hydrostatic equilibrium and (iii) cluster substructure fraction is also correlated with the slope of the gas density profile on small scales, implying a connection between cluster–cluster mergers and gas cooling. Overall our results are consistent with the view that cluster–cluster mergers play a prominent role in shaping the properties of cluster cores, in particular causing departures from hydrostatic equilibrium, and possibly disturbing cool cores. Our results do not support recent claims that large Einstein radius clusters present a challenge to the cold dark matter paradigm.

Subfields: Astronomy and Astrophysics, Instrumentation

View Paper: https://www.semanticscholar.org/paper/2ae1ce3a1f9c5a4aad6f736657b1e476615ab6ec

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Astronomy and Astrophysics

In Instrumentation

Citations in the corpus

LoCuSS: Subaru Weak Lensing Study of 30 Galaxy Clusters (2009, methodology): “We are also testing this more thoroughly with our new HST data (SNAP:10881; Hamilton-Morris et al. in preparation, and GO:11312; Richard et al. 2010) and the new Bayesian version of lenstool (Jullo & Kneib 2009).”
Cosmological simulations with self-interacting dark matter – II. Halo shapes versus observations (2012, methodology): “3 of Richard et al. (2010).”
THE INTERSTELLAR MEDIUM IN DISTANT STAR-FORMING GALAXIES: TURBULENT PRESSURE, FRAGMENTATION, AND CLOUD SCALING RELATIONS IN A DENSE GAS DISK AT z = 2.3 (2011, methodology): “The cluster lensing model for MACSJ2135-0102 is derived using the lenstool code (Kneib et al. 1996; Jullo et al. 2007) which employs a parametric model of the mass distribution (Richard et al. 2009, 2010).”
THE DENSITY PROFILES OF MASSIVE, RELAXED GALAXY CLUSTERS. I. THE TOTAL DENSITY OVER THREE DECADES IN RADIUS (2012, methodology): “The center, ellipticity, and P.A. are fixed to that of the light, and for most of the cluster galaxies, the structural parameters are tied to scaling relations specific to each cluster (e.g., Limousin et al. 2007; N09; Richard et al. 2010): rcut = rcut,∗(Lr/Lr,∗) 1/2 rcore = rcore,∗(Lr/Lr,∗) 1/2 σ =”
THE CLUSTER LENSING AND SUPERNOVA SURVEY WITH HUBBLE: AN OVERVIEW (2011, methodology): “…Foley et al. 2011) and the finding that some clusters at intermediate redshift (z ∼ 0.3) have denser cores than clusters of similar mass produced in simulations (Broadhurst et al. 2008; Broadhurst & Barkana 2008; Oguri et al. 2009; Richard et al. 2010; Sereno et al. 2010; Zitrin et al. 2011a).”
Are Brightest Halo Galaxies Central Galaxies (2010, background): “This ignores the fact that dark matter haloes are believed to have a wealth of substructure (see Giocoli et al. 2010, and references therein; on substructure in galaxy clusters, see Richard et al. 2010).”
The Frontier Fields lens modelling comparison project (2016, background): “In several cases strong-lensing masses for the same cluster lens were found to be in tension (by a factor 2-3) with other independent measurements, based e.g on the modeling of the X-ray emission by the intracluster gas (Ebeling et al. 2009; Richard et al. 2010; Donahue et al. 2014).”
Ultraviolet emission lines in young low-mass galaxies at z ≃ 2: physical properties and implications for studies at z > 7 (2014, methodology): “The mass model in Abell 68 is described in Richard et al. (2007) and Richard et al. (2010), while the MACS 0451 mass c© 2013 RAS, MNRAS000, 1–22 model is based on that presented in Jones et al. (2010), updated to include the new multiple images presented in this work.”
KECK SPECTROSCOPY OF FAINT 3 < z < 8 LYMAN BREAK GALAXIES: EVIDENCE FOR A DECLINING FRACTION OF EMISSION LINE SOURCES IN THE REDSHIFT RANGE 6 < z < 8 (2011, methodology): “We estimate the luminosities of all our sources in Table 1 from their photometric redshift and incorporate the lensing magnification µ for our lensed sources from Bradley et al. (2011) for Abell 1703 and from the mass model of Richard et al. (2010) for MS0451-03 and Abell 2261.”
Mass and magnification maps for the Hubble Space Telescope Frontier Fields clusters: implications for high-redshift studies (2014, methodology): “Following our successful strategy from previous lensing work (e.g. Limousin et al. 2007, 2012; Richard et al. 2010a,b), we adopt a parametric model combining both large-scale (cluster or group size) mass clumps as well as galaxy-scale mass clumps.”
HUBBLE SPACE TELESCOPE COMBINED STRONG AND WEAK LENSING ANALYSIS OF THE CLASH SAMPLE: MASS AND MAGNIFICATION MODELS AND SYSTEMATIC UNCERTAINTIES (2014, background): “…placed on the mass distribution and profile (Kneib et al. 2004; Broadhurst et al. 2005; Smith et al. 2005; Limousin et al. 2008; Newman et al. 2009; Richard et al. 2010, 2014; Bradač et al. 2008; Liesenborgs et al. 2008; Diego et al. 2005, 2015b, 2015a; Coe et al. 2010; Oguri et al. 2013; Sereno…”
Combined strong and weak lensing analysis of 28 clusters from the Sloan Giant Arcs Survey (2011, background): “High concentrations can be tested with the distribution of the Einstein radii, but the results have still not converged (Broadhurst & Barkana 2008; Oguri & Blandford 2009; Richard et al. 2010; Gralla et al. 2011; Zitrin et al. 2011a,c).”
X-ray–optical classification of cluster mergers and the evolution of the cluster merger fraction (2011, methodology): “…galaxies and dark matter has yielded compelling observational evidence of the existence of dark matter (Clowe et al. 2006; Limousin et al. 2010; Richard et al. 2010) and has, in addition, been used to place upper limits on the dark matter self-interaction cross-section, σ /m, of the putative…”