QUBIC VIII: Optical design and performance

O'SULLIVAN, C.; CLAUDIA G. SCOCCOLA; AND THE QUBIC COLLABORATION

JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS

IOP PUBLISHING LTD

Lugar: Londres; Año: 2021

1475-7516

The Q and U Bolometric Interferometer for Cosmology (QUBIC) is a ground-basedexperiment that aims to detect B-mode polarisation anisotropies in the CMB atangular scales around the l=100 recombination peak. Systematic errors makeground-based observations of B modes at millimetre wavelengths very challengingand QUBIC mitigates these problems in a somewhat complementary way to otherexisting or planned experiments using the novel technique of bolometricinterferometry. This technique takes advantage of the sensitivity of an imagerand the systematic error control of an interferometer. A cold reflectiveoptical combiner superimposes there-emitted beams from 400 aperture feedhornson two focal planes. A shielding system composedof a fixed groundshield, and aforebaffle that moves with the instrument, limits the impact of localcontaminants. The modelling, design, manufacturing and preliminary measurementsof the optical components are described in this paper.