An empirical method for mitigating an excess up-scattering mass bias on the weak lensing mass estimates for shear-selected cluster samples

Abstract

An excess up-scattering mass bias on a weak lensing cluster mass estimate is a statistical bias that an observed weak lensing mass ($M_{\mathrm{obs}}$) of a cluster of galaxies is, in a statistical sense, larger than its true mass ($M_{\mathrm{true}}$) because of a higher chance of up-scattering than that of down-scattering due to random noises in a weak lensing cluster shear profile. This non-symmetric scattering probability is caused by a monotonically decreasing cluster mass function with increasing mass. We examine this bias (defined by $b=M_{\mathrm{obs}}/M_{\mathrm{true}}$) in weak lensing shear-selected clusters, and present an empirical method for mitigating it. In so doing, we perform the standard weak lensing mass estimate of realistic mock clusters, and find that the weak lensing mass estimate based on the standard ${\chi }^2$ analysis gives a statistically correct confidence intervals, but resulting best-fitting masses are biased high on average. Our correction method uses the framework of the standard Bayesian statistics with the prior of the probability distribution of the cluster mass and concentration parameter from recent empirical models. We test our correction method using mock weak lensing clusters, and find that the method works well with resulting corrected $M_{\mathrm{obs}}$-bin averaged mass biases being close to unity within $\sim 10$ percent. We applied the correction method to weak lensing shear-selected cluster sample of Hamana et al. (2020), and present bias-corrected weak lensing cluster masses.

16 pages, 10 figures, version matches that published in PASJ. The bias corrected masses of HSC survey S19A shear selected clusters (Oguri et al 2021) are available from http://th.nao.ac.jp/MEMBER/hamanatk/HSC19aWLCusters/s19a_TI05_exupscat_bias_corr_ML_MP.dat

References in corpus (14)

• Combining Strong and Weak Gravitational Lensing in Abell 1689
• The galaxy cluster mass scale and its impact on cosmological constraints from the cluster population
• Comparison of weak lensing masses and X-ray properties of galaxy clusters
• A cluster finding algorithm based on the multiband identification of red sequence galaxies
• Analytic models of plausible gravitational lens potentials
• Full-sky Gravitational Lensing Simulation for Large-area Galaxy Surveys and Cosmic Microwave Background Experiments
• Combining Lens Distortion and Depletion to Map the Mass Distribution of A1689
• A Statistical Study of Weak Lensing by Triaxial Dark Matter Halos: Consequences for Parameter Estimation
• The eROSITA Final Equatorial-Depth Survey (eFEDS): X-ray Observable-to-Mass-and-Redshift Relations of Galaxy Clusters and Groups with Weak-Lensing Mass Calibration from the Hyper Suprime-Cam Subaru Strategic Program Survey
• Cosmic variance of the galaxy cluster weak lensing signal
• Cosmological constraints from Subaru weak lensing cluster counts
• XXL Survey groups and clusters in the Hyper Suprime-Cam Survey. Scaling relations between X-ray properties and weak lensing mass
• Hundreds of weak lensing shear-selected clusters from the Hyper Suprime-Cam Subaru Strategic Program S19A data
• The eROSITA Final Equatorial-Depth Survey (eFEDS): A complete census of X-ray properties of Subaru Hyper Suprime-Cam weak lensing shear-selected clusters in the eFEDS footprint

Cited by in corpus (2)

• Peaks in weak lensing mass maps for cluster astrophysics and cosmology
• The uncommon intracluster medium features of the first massive clusters selected independently of their baryon content