The QUBIC experiment

schematic of the  QUBIC instrument

 

QUBIC is an experiment based on the concept of bolometric interferometry and designed to constrain tightly the B-mode polarization anisotropies  of the Cosmic Microwave Background.

B-mode searches need multi-frequency sensitive instruments to control  foreground contamination, and an unprecedented level of control of  systematic effects that should be designed in-hardware, as much as possible.

QUBIC is designed to address all aspects of this challenge with a novel kind of instrument, a Bolometric Interferometer, combining the background-limited sensitivity of Transition-Edge-Sensors and the control of systematics allowed by the observation of interference fringe patterns, while operating at two frequencies to disentangle polarized foregrounds from primordial B mode polarization.

QUBIC is the only European ground based B-mode project with the scientific potential of discovering and measuring B-modes. It is the natural project for the European CMB community to continue at the edge cutting level it has reached with Planck.

The first QUBIC module will operate from the ground observing the sky in two spectral bands centred at 150 and 220 GHz and will be deployed in Argentina, at the Alto Chorillo site.

 

Caption: Left: QUBIC aperture plane showing all 400 antennas open to the sky. Right: the interference pattern formed on each of the focal  planes when the instrument is observing a far point source located along the instrument line-of-sight.