Brightest Cluster Galaxies Trace Weak Lensing Mass Bias and Halo Triaxiality in The Three Hundred Project

Abstract

Galaxy clusters have a triaxial matter distribution. The weak-lensing signal, an important part in cosmological studies, measures the projected mass of all matter along the line-of-sight, and therefore changes with the orientation of the cluster. Studies suggest that the shape of the brightest cluster galaxy (BCG) in the centre of the cluster traces the underlying halo shape, enabling a method to account for projection effects. We use 324 simulated clusters at four redshifts between 0.1 and 0.6 from `The Three Hundred Project' to quantify correlations between the orientation and shape of the BCG and the halo. We find that haloes and their embedded BCGs are aligned, with an average $\sim$20 degree angle between their major axes. The bias in weak lensing cluster mass estimates correlates with the orientation of both the halo and the BCG. Mimicking observations, we compute the projected shape of the BCG, as a measure of the BCG orientation, and find that it is most strongly correlated to the weak-lensing mass for relaxed clusters. We also test a 2-dimensional cluster relaxation proxy measured from BCG mass isocontours. The concentration of stellar mass in the projected BCG core compared to the total stellar mass provides an alternative proxy for the BCG orientation. We find that the concentration does not correlate to the weak-lensing mass bias, but does correlate with the true halo mass. These results indicate that the BCG shape and orientation for large samples of relaxed clusters can provide information to improve weak-lensing mass estimates.

15 pages, 9 figures, Figure 7 is key plot, Updated to match version accepted by MNRAS

References in corpus (38)

• scikit-image: Image processing in Python
• The hierarchical formation of the brightest cluster galaxies
• Weighing the Giants IV: Cosmology and Neutrino Mass
• The Atacama Cosmology Telescope: A Catalog of > 4000 Sunyaev-Zel'dovich Galaxy Clusters
• An excess of small-scale gravitational lenses observed in galaxy clusters
• Analytic models of plausible gravitational lens potentials
• The MUSIC of CLASH: predictions on the concentration-mass relation
• Brightest Cluster Galaxies at the Present Epoch
• Galaxies in X-ray Groups. II. A Weak Lensing Study of Halo Centering
• Cosmology and Astrophysics from Relaxed Galaxy Clusters I: Sample Selection
• Cosmological Constraints from DES Y1 Cluster Abundances and SPT Multi-wavelength data
• Dark Energy Survey Year 1 Results: Cosmological Constraints from Cluster Abundances, Weak Lensing, and Galaxy Correlations
• The impact of baryons on massive galaxy clusters: halo structure and cluster mass estimates
• The Three Hundred Project: Backsplash galaxies in simulations of clusters
• Some like it triaxial: the universality of dark matter halo shapes and their evolution along the cosmic time
• Dark Energy Survey Year 1 Results: Calibration of Cluster Mis-centering in the redMaPPer Catalogs
• The Three Hundred Project: Dynamical state of galaxy clusters and morphology from multi-wavelength synthetic maps
• AMICO galaxy clusters in KiDS-DR3: cosmological constraints from counts and stacked weak-lensing
• A Hard X-ray Test of HCN Enhancements as a Tracer of Embedded Black Hole Growth
• Cosmological Constraints from Gas Mass Fractions of Massive, Relaxed Galaxy Clusters
• Orientation Bias of Optically Selected Galaxy Clusters and Its Impact on Stacked Weak Lensing Analyses
• Shapes and alignments of dark matter haloes and their brightest cluster galaxies in 39 strong lensing clusters
• The Distribution of Satellites Around Central Galaxies in a Cosmological Hydrodynamical Simulation
• The Three Hundred Project: quest of clusters of galaxies morphology and dynamical state through Zernike Polynomials
• Mass calibration of distant SPT galaxy clusters through expanded weak lensing follow-up observations with HST, VLT & Gemini-South
• The Three Hundred project: shapes and radial alignment of satellite, infalling, and backsplash galaxies
• Brightest Cluster Galaxies: the centre can(not?) hold
• The WaZP galaxy cluster sample of the Dark Energy Survey Year 1
• The Three Hundred Project: the stellar and gas profiles
• AMICO galaxy clusters in KiDS-DR3: cosmological constraints from large-scale stacked weak lensing profiles
• Evolution and Role of Mergers in the BCG-Cluster Alignment. A View from Cosmological Hydro-Simulations
• The Observed Evolution of the Stellar Mass - Halo Mass Relation for Brightest Central Galaxies
• SHAPing the Gas: Understanding Gas Shapes in Dark Matter Haloes with Interpretable Machine Learning
• Stellar and Weak Lensing Profiles of Massive Galaxies in the Hyper-Suprime Cam Survey and in Hydrodynamic Simulations
• An Optimal Estimator of Intrinsic Alignments for Star-forming Galaxies in IllustrisTNG Simulation
• Ellipticity of Brightest Cluster Galaxies as tracer of halo orientation and weak-lensing mass bias
• The link between brightest cluster galaxy properties and large scale extensions of 38 DAFT/FADA and CLASH clusters in the redshift range 0.2<z<0.9
• The effect of selection -- a tale of cluster mass measurement bias induced by correlation and projection

Cited by in corpus (10)

• A persistent excess of galaxy-galaxy strong lensing observed in galaxy clusters
• Euclid preparation. XXXII. Evaluating the weak lensing cluster mass biases using the Three Hundred Project hydrodynamical simulations
• The Three Hundred Project: the evolution of physical baryon profiles
• Euclid preparation: Determining the weak lensing mass accuracy and precision for galaxy clusters
• The Three Hundred Project: Mapping The Matter Distribution in Galaxy Clusters Via Deep Learning from Multiview Simulated Observations
• Intrinsic mass-richness relation of clusters from THE THREE HUNDRED hydrodynamic simulations
• Galaxy cluster mass bias from projected mass maps: The Three Hundred-NIKA2 LPSZ twin samples
• A CMB lensing analysis of the extended mass distribution of clusters
• Estimating the triaxiality of massive clusters from 2D observables in MillenniumTNG with machine learning
• Deep Learning generated observations of galaxy clusters from dark-matter-only simulations