Detectability of 21cm signal during the Epoch of Reionization with 21cm-LAE cross correlation
Wed 11 July, 2018 @12:00 PM, level 7
The 21cm signal is a powerful tool to probe the Epoch of Reionization. However the detection of the redshifted 21cm signal is difficult due to the bright foregrounds. For mitigating the foreground contamination, the cross correlation with other observable is useful. Here, we predict the detectability of the cross power spectrum between 21cm signal and Lyman-alpha emitter (LAE) by using numerical reionization simulation and assuming ongoing and future observations. For 21cm observation, we assume radio survey by the Murchison Widefield Array (MWA) and Square Kilometre Array (SKA). The LAEs are detected at z=5.7, 6.6 and 7.3 by Subaru Hyper Suprime-Cam (HSC). In this work, we find that the MWA can detect the signal by combining the spectroscopic survey with the Prime Focus Spectrograph (PFS). In practice, however, the error of cross power spectrum is dominated by the foregrounds, and moderate foreground removal is required.