Detection Feasibility of Cluster-Induced CMB Polarization.
Galaxy clusters can potentially induce sub-$\mu$K polarization signals in the CMB with characteristic scales of a few arcminutes in nearby clusters. We explore four such polarization signals induced in a rich nearby cluster and calculate the likelihood for their detection by the currently operational SPTpol, advanced ACTpol, and the upcoming Simons Array. In our feasibility analysis we include instrumental noise, primordial CMB anisotropy, statistical thermal SZ cluster signal, and point source confusion, assuming a few percent of the nominal telescope observation time of each of the three projects. Our analysis indicates that the thermal SZ intensity can be easily mapped in rich nearby clusters, and that the kinematic SZ intensity can be measured with high statistical significance toward a fast moving nearby cluster. The detection of polarized SZ signals will be quite challenging, but could still be feasible towards several very rich nearby clusters with exceptionally high SZ intensity. The polarized SZ signal from a sample of $\sim 20$ clusters can be statistically detected at $S/N \sim 3$, if observed for several months.
Publisher URL: http://arxiv.org/abs/1711.03079