MRI-R2: Development of a Low-Frequency Microwave Polarimeter for Large Scale Surveys

Johns Hopkins University, Baltimore MD

Investigators

Abstract

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). Throughout history and all cultures mankind has wondered about the beginnings of our universe. Today's scientific understanding of those beginnings still leaves many unanswered questions: Why is the geometry of the universe so flat? Why is the universe so homogeneous? Theoretical cosmologists have posed answers to these questions, but the theories are extremely difficult to verify. Inflation in the very early universe is now the widely accepted theoretical explanation, but empirical measurements of the subtle predictions of inflation theory are elusive. Dr. Charles Bennett of The Johns Hopkins University is building a sophisticated instrument to make a measurement of the very faint imprint on the Cosmic Microwave Background (CMB) that inflation theory predicts would have been made by gravitational waves. The key is to measure the anisotropy of the so-called "B mode polarization" in the CMB. This is a search for a veritable needle in a haystack and great care is required to detect and isolate the very weak distant signature from the very strong unrelated foreground signals on the sky. Dr. Bennett has designed an instrument that he suggests stands the best chance for making this measurement by targeting the scales where the signature is strongest relative to the foreground signals. Development of this instrument is funded by the National Science Foundation's Major Research Instrumentation program through the Division of Astronomical Sciences.