Transition-edge Sensor Detectors to Enable Characterization of the Cosmic Microwave Background
This blog post originated in the 2017 Science Mission Directorate Technology Highlights Report (33 MB PDF). Technology Development Relic radiation from the Big Bang—the Cosmic Microwave Background (CMB)—provides a Rosetta stone for deciphering the content, structure, and evolution of the early universe. Current theoretical understanding suggests that the universe underwent a rapid exponential expansion, called “inflation,” in the first fraction of a second. Such an event would result in an observable stochastic background of gravitational waves that impresses a faint polarized signature on the CMB. The National Research Council’s decadal survey recommended characterization of the CMB as a high-priority science objective, but measurement of the polarization signature is very difficult because it is so faint—about 10-8 of the 2.725 K isotropic component of the CMB. The 40 GHz focal plane during assembly (top) and a completed 90 GHz focal plane (bottom). Both have been deployed to Chile for observations of the cosmic microwave background. Not only would...