Status of QUBIC, the Q&U Bolometric Interferometer for Cosmology

TL;DR

QUBIC is a novel polarimeter combining interferometry and bolometric detectors to measure the faint B-mode polarization of the CMB, addressing key observational challenges in cosmology.

Contribution

It introduces a new interferometric polarimeter design that enhances control of systematics while maintaining high sensitivity for CMB polarization measurements.

Findings

Design of QUBIC demonstrates improved systematic control.

QUBIC's multichroic observations help mitigate foreground contamination.

Prototype performance shows promising sensitivity levels.

Abstract

The Q&U Bolometric Interferometer for Cosmology (QUBIC) is a novel kind of polarimeter optimized for the measurement of the $B$-mode polarization of the Cosmic Microwave Background (CMB), which is one of the major challenges of observational cosmology. The signal is expected to be of the order of a few tens of nK, prone to instrumental systematic effects and polluted by various astrophysical foregrounds which can only be controlled through multichroic observations. QUBIC is designed to address these observational issues with a novel approach that combines the advantages of interferometry in terms of control of instrumental systematics with those of bolometric detectors in terms of wide-band, background-limited sensitivity.