http://arxiv.org/abs/2201.01643
By stacking the latest 217~GHz Planck PR4 map at the positions of 30,431 galaxy clusters from the Wen-Han-Liu (WHL) catalog, we report the detection of the kinetic Sunyaev-Zel’dovich (kSZ) effect in galaxy clusters with a 4.9 sigma significance level and beyond 3xR500. The line of sight velocities of galaxy clusters were estimated with a machine-learning approach, in which the relation between the galaxy distribution around a cluster and its line-of-sight velocity was trained through a convolutional neural network using the simulated galaxies and galaxy clusters in the Magneticum cosmological hydrodynamic simulations. The trained model was applied to the large-scale distribution of the Sloan Digital Sky Survey galaxies to derive the line-of-sight velocities of the WHL galaxy clusters. Assuming a standard beta-model for the intracluster medium, we found that the gas fraction within R500 is fgas,500 = 0.09+-0.02 for the clusters with the mass of M500~1.0×10^14 Msun.
H. Tanimura, N. Aghanim, V. Bonjean, et. al.
Thu, 6 Jan 22
19/56
Comments: 8 pages, 6 figures, submitted to A&A. arXiv admin note: text overlap with arXiv:2007.02952