Research

An experiment located in the Atacama Desert in Chile, this project was designed to map the faint B-mode polarization signal from the cosmic polarization background (CMB). The first stage of the project was POLARBEAR-1, which started observing in 2012, leading to the detection of B-mode polarization from gravitational lensing of the CMB in 2014.  Building on that success, our team is working on commissioning POLARBEAR-2, which includes powerful new telescopes that are highly sensitive and can cover a large portion of the sky. This project, supported by the Simons Foundation and the National Science Foundation, will produce a detailed survey of CMB polarization, expanding our knowledge of the universe and its formation. 

Atmospheric and RFI Monitoring on Cerro Toco

As we work to create precision maps of the sky in temperature and polarization across a broad range of microwave frequencies, these extremely sensitive instruments are vulnerable to radio frequency interference (RFI) from nearby sources of microwave emission. Funded by the National Science Foundation, we are working on developing better tools to monitor and understand the microwave environment and micro-climate on Cerro Toco, the site of POLARBEAR/Simons Array and future instruments like Simons Observatory and CMB-S4. In planning for the next generation of CMB surveys, stray microwave emission from large communication satellite constellations is an emerging threat that we are working on understanding and mitigating.