The search for gravitational waves has long been the cornerstone of cosmology and astrophysics since Einstein proposed the general relativity in early 20th century. Detection of primordial gravitational waves (PGWs) would be one of the most significant scientific discoveries. The most effective way for probing PGWs is measuring B-mode polarization of cosmic microwave background radiation (CMB). However, astrophysical foreground contamination is much larger than signals, and so is an unavoidable challenge of detecting primordial B-modes. In this talk, the speaker will first make a general introduction to the project of Ali CMB Polarization Telescope (Ali-CPT) and then review some statistical methods used in CMB foreground removal, including “blind” and “non-blind” source separation techniques.
