Speaker
Description
The unprecedented depth of current-generation CMB experiments enabled a window into studying the thermal Sunyaev-Zeldovich (tSZ) effect in a once inaccessible population of galaxy clusters. The newest instrument on the South Pole Telescope, SPT-3G, has produced CMB maps with noise levels of 3.2, 2.5, and 8.9 μK-arcmin at 95, 150, and 220 GHz, respectively. This has allowed for the detection of over 7,200 clusters with masses ranging from 7.9x10^{13} to 1.6x10^{15} in the redshift range 0.037 < z < ~2. The cluster sample detected in high-resolution SPT-3G maps will enable high-precision cross-validation with optical and X-ray cluster catalogs, and combined with optical weak lensing measurements from wide-field surveys, offer new leverage on cosmological constraints derived from cluster abundances. SZ cluster cosmology is now also being internally validated through CMB-only probes, including constraints on the tSZ–mass relation from cluster masses inferred via the lensing of the CMB by galaxy clusters, and measurements of the bias parameter from the clustering of galaxy clusters. Future analyses using the full 10,000 deg² SPT-3G survey, leveraging a substantially larger cluster sample, will yield increasingly precise and self-consistent constraints on cosmology from cluster abundances.
| Other topic / keywords: | Galaxy Clusters, Cosmology |
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