Princeton University Gravity Group Seminar

At the focus of the Simons Observatory telescopes, the Universal Focal-Plane Modules (UFMs) will detect and modulate the cosmic microwave background (CMB) signal using a Microwave SQUID Multiplexing (uMux) readout architecture. This novel readout design enables the simultaneous interrogation of 910 transition-edge sensor (TES) detectors with a single pair of coaxial cables by coupling each detector to a microwave resonator with a unique frequency between 4 and 6 GHz. The breakthrough multiplexing factor (910x) is two orders of magnitude higher than alternative readout architectures for TESes, which have become the standard detector choice for CMB instrumentation. I will describe the uMux implementation for Simons Observatory, discuss the design of the UFMs, and show results from the early production arrays.