Cosmic Microwave Background

The Cosmic Microwave Background (CMB) provides the earliest possible image of the Universe, as it was only 370,000 years after the Big Bang. Redshifted 1100-fold since then, this ancient signal is so cold and faint that making an image of it requires experiments to gather trillions of observations which are then reduced to maps of tens of millions of pixels using the most powerful high performance computing (HPC) facilities.

The C³ CMB group works in several interconnected areas:

• Generalizing the problem of CMB map-making to the reduction of any pointed time-domain data, and ensuring that the analysis of exponentially growing datasets scales to the largest HPC systems available, through the development of Time-Ordered Astrophysics Scalable Tools (TOAST).
• Applying TOAST-based codes to the analysis of data from the current Planck satellite, POLARBEAR ground-based and EBEX long-duration balloon experiments, and proposed next-generation projects like CMB-S4, LiteBIRD and COrE+.
• Tackling the most computationally challenging time-domain analyses, including the generation of Monte Carlo simulation sets, and keeping the resulting FFP MC datasets, and the public Planck releases they correspond to spinning and publically available on the NERSC /project filesystem.  
• Supporting the overall US CMB data analysis community through the management and maintenance of HPC resources for CMB data analysis at NERSC, including general and experiment-specific software modules and dedicated project data spaces.
• Using the most computationally demanding CMB codes for HPC whole-system performance analysis and co-design.