Tibet's Ali: A New Window to Detect the CMB Polarization

Understand

The Cosmic Microwave Background (CMB) Polarization plays an important role in current cosmological studies.

• CMB B-mode polarization is the most effective probe to primordial gravitational waves (PGWs) and a test of the inflation as well as other theories of the early universe such as bouncing and cyclic universe.
• So far, major ground-based CMB polarization experiments are located in the southern hemisphere.Recently, China has launched the Ali CMB Polarization Telescope (AliCPT) in Tibetan Plateau to measure CMB B mode polarization and detect the PGWs in northern hemisphere.
• AliCPT include two stages, the first one is to build a telescope at the 5250m site (AliCPT-1) and the second one is to have a more sensitive telescope at a higher altitude of about 6000m (AliCPT-2).