The Sunyaev-Zeldovich Signal of the maxBCG SDSS Galaxy Clusters in WMAP

Understand

The Planck Collaboration measured the Sunyaev-Zel'dovich (SZ) decrement of optically selected clusters from the Sloan Digital Sky Survey, finding that it falls significantly below expectations based on existing mass calibration of the maxBCG galaxy clusters.

• Resolving this tension requires either the data to go up, or the theoretical expectations to come down.
• Here, we use data from the Wilkinson Microwave Anisotropy Probe (WMAP) to perform an independent estimate of the SZ decrement of maxBCG clusters.
• The recovered signal is consistent with that obtained using Planck, though with larger error bars due to WMAP's larger beam size and smaller frequency range.