The Primordial Inflation Polarization ExploreR (PIPER) is a balloon-borne telescope designed to measure the polarization of the Cosmic Microwave Background on large angular scales. PIPER will map 85% of the sky at 200, 270, 350, and 600 GHz over a series of 8 conventional balloon flights from the northern and southern hemispheres. The first science flight will use two 32 × 40 arrays of backshort-under-grid transition edge sensors, multiplexed in the time domain, and maintained at 100 mK by a Continuous Adiabatic Demagnetization Refrigerator. Front- end cryogenic Variable-delay Polarization Modulators provide systematic control by rotating linear to circular polarization at 3 Hz. Twin telescopes allow PIPER to measure Stokes I, Q, U , and V simultaneously. The telescope is maintained at 1.5 K in an LHe bucket dewar. Cold optics and the lack of a warm window permit sensitivity at the sky-background limit. The ultimate science target is a limit on the tensor-to-scalar ratio of r ∼ 0.007, from the reionization bump to l ∼ 300. PIPER’s first flight will be from the Northern hemisphere, and overlap with the CLASS survey at lower frequencies. We describe the current status of the PIPER instrument.

Date Published: 19 July 2016
PDF: 8 pages
Proc. SPIE 9914, Millimeter, Submillimeter, and Far-Infrared Detectors and Instrumentation for Astronomy VIII, 99141J (19 July 2016); doi: 10.1117/12.2231109

Published in SPIE Proceedings Vol. 9914:
Millimeter, Submillimeter, and Far-Infrared Detectors and Instrumentation for Astronomy VIII
Wayne S. Holland; Jonas Zmuidzinas, Editor(s)