Sesto

Date:

I attended the meeting in Sesto, Italy. Tracing cosmic evolution with clusters of galaxies is a conference on the physics of galaxy clusters in theoretical simulations and multiwavelength observations. I presented a talk on the progress of weak lensing masses for a sample of 100 clusters and the difficulty in obtaining accurate mass estimates with weak lensing when statistical errors are decreasing. I specifically addressed selection biases that may arise when the selection of the clusters depends on the orientation of the halo.

abstract

In principle weak lensing can produce unbiased mass estimates of galaxy clusters, which are used in cosmological analyses and comparisons to other mass estimates used to further understand cluster physics. However, in practice, weak lensing is a difficult method that suffers from large statistical uncertainties. In our work we have performed a weak lensing analysis on excellent quality, deep optical imaging for a sample of 100 clusters spanning a large range in masses and redshift, making it ideal for scaling relations with other mass probes. All sources of systematics are carefully treated. Issues with the source redshift distribution are handled using ancillary optical data and state-of-the-art hydrodynamical simulations were consulted to estimate the robustness of the mass estimates. We compare our masses to re-extracted measurements of the Planck observations and available gas mass estimates.

PDF of the presentation