A Polarization Modulator Unit for the Mid- and High-Frequency Telescopes of the LiteBIRD mission [article]

Fabio Columbro, Paolo de Bernardis, Luca Lamagna, Silvia Masi, Alessandro Paiella, Francesco Piacentini, Giampaolo Pisano
2021 arXiv   pre-print
The LiteBIRD mission is a JAXA strategic L-class mission for all sky CMB surveys which will be launched in the 2020s. The main target of the mission is the detection of primordial gravitational waves with a sensitivity ofthe tensor-to-scalar ratio δr <0.001. The polarization modulator unit (PMU) represents a critical and powerful component to suppress 1/f noise contribution and mitigate systematic uncertainties induced by detector gain drift, both for the high-frequency telescope (HFT) and for
more » ... he mid-frequency telescope (MFT). Each PMUs based on a continuously-rotating transmissive half-wave plate (HWP) held by a superconducting magnetic bearing in a 5K environment. In this proceeding we will present the design and expected performance of the LiteBIRD PMUs and testing performed on every PMU subsystem with a room-temperature rotating disk used as a stand-in for the cryogenic HWP rotor.
arXiv:2101.05188v1 fatcat:f3nzkfwrynginf2tr3f66tkdwi