Understanding the large inferred Einstein radii of observed low-mass galaxy clusters
arXiv:2002.09494 · doi:10.1093/mnras/staa1076
Abstract
We assess a claim that observed galaxy clusters with mass ~10^14 Msun are more centrally concentrated than predicted in LCDM. We generate mock strong gravitational lensing observations, taking the lenses from a cosmological hydrodynamical simulation, and analyse them in the same way as the real Universe. The observed and simulated lensing arcs are consistent with one another, with three main effects responsible for the previously claimed inconsistency. First, galaxy clusters containing baryonic matter have higher central densities than their counterparts simulated with only dark matter. Second, a sample of clusters selected because of the presence of pronounced gravitational lensing arcs preferentially finds centrally concentrated clusters with large Einstein radii. Third, lensed arcs are usually straighter than critical curves, and the chosen image analysis method (fitting circles through the arcs) overestimates the Einstein radii. After accounting for these three effects, LCDM predicts that galaxy clusters should produce giant lensing arcs that match those in the observed Universe.
arXiv comment8 pages, 3 figures, updated to match MNRAS version
References in corpus (30)
- A Universal Density Profile from Hierarchical Clustering
- The cosmological simulation code GADGET-2
- Nine-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Cosmological Parameter Results
- The effect of photo-ionization on the cooling rates of enriched, astrophysical plasmas
- Response of dark matter halos to condensation of baryons: cosmological simulations and improved adiabatic contraction model
- Cosmological simulations of the growth of supermassive black holes and feedback from active galactic nuclei: method and tests
- The physics driving the cosmic star formation history
- The Fifth Data Release of the Sloan Digital Sky Survey
- Chemical enrichment in cosmological, smoothed particle hydrodynamics simulations
- On the relation between the Schmidt and Kennicutt-Schmidt star formation laws and its implications for numerical simulations
- The BAHAMAS project: Calibrated hydrodynamical simulations for large-scale structure cosmology
- Simulating galactic outflows with kinetic supernova feedback
- The Size Evolution of High Redshift Galaxies
- The Mass-Concentration-Redshift Relation of Cold and Warm Dark Matter Halos
- Combined strong and weak lensing analysis of 28 clusters from the Sloan Giant Arcs Survey
- CLASH: The Concentration-Mass Relation of Galaxy Clusters
- Geometry of Star-Forming Galaxies from SDSS, 3D-HST and CANDELS
- The BAHAMAS project: the CMB--large-scale structure tension and the roles of massive neutrinos and galaxy formation
- Comparison of Cluster Lensing Profiles with Lambda CDM Predictions
- Observable tests of self-interacting dark matter in galaxy clusters: cosmological simulations with SIDM and baryons
- Giant cluster arcs as a constraint on the scattering cross-section of dark matter
- Strong Lens Models for 37 Clusters of Galaxies from the SDSS Giant Arcs Survey
- Arc Statistics
- The strongest gravitational lenses: I. The statistical impact of cluster mergers
- The Sloan Bright Arcs Survey : Six Strongly Lensed Galaxies at z=0.4-1.4
- On the over-concentration problem of strong lensing clusters
- Merging Galaxies in the SDSS EDR
- Effects of the halo concentration distribution on strong-lensing optical depth and X-ray emission
- Are group- and cluster-scale dark matter halos over-concentrated?
- The Sloan Bright Arcs Survey: Ten Strong Gravitational Lensing Clusters and Evidence of Overconcentration