Detecting Inflationary Gravitational Waves by Realizing Removal of Lensing Contaminants in Cosmic Microwave Background B-modes: Simons Observatory Case

I present my recent efforts on establishing methodology for removing lensing noise (delensing) to detect primordial gravitational waves (GWs) from cosmic microwave background (CMB). One of the promising cosmological probes in the next decades is the twisting pattern in the CMB polarization map (B-modes) which will be a unique way to explore the early universe through GWs. In this talk, I show successful delensing algorithm which works even in practical situations for the Simons Observatory such as the presence of inhomogeneous noise and masking. The expected constraints on the amplitude of the primordial GWs by delensing would be improved by a nearly factor 2 compared to that without delensing.