The LiteBIRD mission is a next generation CMB space mission which aims at detecting CMB polarization produced by primordial gravitational waves, with a sensitivity for the tensor to scalar ratio δr < 0.001. A polarization modulator unit (PMU) represents a critical and powerful component to avoid 1/f noise contributions and mitigate differential systematic uncertainties in orthogonal polarization sensitive detectors on both Mid- and High- Frequency Telescopes. Each PMU is based on a continuously transmissive rotating half-wave plate (HWP), held by a superconducting magnetic bearing operating in the 5 K environment. The dynamical behaviour of the system during the rotation must be monitored, since it can introduce systematic effects during the measurements. In this contribution, we present the development of custom cryogenic capacitive sensors, used to monitor the spinning rotor. A set of these sensors allows to monitor the levitation height and wobbling of the rotor, with accuracy of ∼ 5 µm and ∼ 0.1′, respect
Capacitive sensors for the polarization modulator unit of the Mid- and High- Frequency Telescopes of LiteBIRD space mission / Columbro, F.; Barbieri Ripamonti, G.; de Bernardis, P.; Coppolecchia, A.; Gorla, G.; Lamagna, L.; Marchitelli, E.; Masi, S.; Occhiuzzi, A.; Paiella, A.; Piacentini, F.; Pisano, G.. - 13102:(2024). (Intervento presentato al convegno Millimeter, Submillimeter, and Far-Infrared Detectors and Instrumentation for Astronomy XII 2024 tenutosi a jpn) [10.1117/12.3019100].
Capacitive sensors for the polarization modulator unit of the Mid- and High- Frequency Telescopes of LiteBIRD space mission
Columbro F.
;de Bernardis P.;Coppolecchia A.;Gorla G.;Lamagna L.;Marchitelli E.;Masi S.;Occhiuzzi A.;Paiella A.;Piacentini F.;Pisano G.
2024
Abstract
The LiteBIRD mission is a next generation CMB space mission which aims at detecting CMB polarization produced by primordial gravitational waves, with a sensitivity for the tensor to scalar ratio δr < 0.001. A polarization modulator unit (PMU) represents a critical and powerful component to avoid 1/f noise contributions and mitigate differential systematic uncertainties in orthogonal polarization sensitive detectors on both Mid- and High- Frequency Telescopes. Each PMU is based on a continuously transmissive rotating half-wave plate (HWP), held by a superconducting magnetic bearing operating in the 5 K environment. The dynamical behaviour of the system during the rotation must be monitored, since it can introduce systematic effects during the measurements. In this contribution, we present the development of custom cryogenic capacitive sensors, used to monitor the spinning rotor. A set of these sensors allows to monitor the levitation height and wobbling of the rotor, with accuracy of ∼ 5 µm and ∼ 0.1′, respectI documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.