QUBIC: The Q&U Bolometric Interferometer for Cosmology - A novel way to look at the polarized Cosmic Microwave Background

In this paper we describe QUBIC, an experiment that takes up the challenge posed by the detection of primordial gravitational waves with a novel approach, that combines the sensitivity of state-of-the art bolometric detectors with the systematic effects control typical of interferometers. The so-called "self-calibration" is a technique deeply rooted in the interferometric nature of the instrument and allows us to clean the measured data from instrumental effects. The first module of QUBIC is a dual band instrument (150 GHz and 220 GHz) that will be deployed in Argentina during the Fall 2018.Fil: Mennella, Aniello. University of Milan; ItaliaFil: Ade, P. A. R.. Cardiff University; Reino UnidoFil: Aumont, J.. Institut d'Astrophysique Spatiale; FranciaFil: Banfie, S.. Istituto Nazionale Di Fisica Nucleare; ItaliaFil: Battaglia, P.. Università degli Studi di Trieste; ItaliaFil: Battistelli, E. S.. Università degli Studi di Roma "La Sapienza"; ItaliaFil: Baùe, F.. Istituto Nazionale Di Fisica Nucleare; ItaliaFil: Buzi, D.. Università degli Studi di Roma "La Sapienza"; ItaliaFil: Columbro, F.. Università degli Studi di Roma "La Sapienza"; ItaliaFil: Bélie, B.. Institute of Fundamental Electronics; FranciaFil: Bennett, D.. Maynooth University; IrlandaFil: Bergé, L.. Centre de Sciences Nucléaires et de Sciences de la Matière; FranciaFil: Bernard, J. Ph.. Institut de Recherche en Astrophysique et Planétologie; FranciaFil: Bersanelli, M.. University of Milan; ItaliaFil: Bigot Sazy, M. A.. APC; FranciaFil: Bleurvacq, N.. APC; FranciaFil: Bordier, G.. APC; FranciaFil: Brossard, J.. APC; FranciaFil: Bunn, E. F.. Richmond University; Estados UnidosFil: Burke, D. P.. Maynooth University; IrlandaFil: Buzi, D.. Università degli Studi di Roma "La Sapienza"; ItaliaFil: Buzzelli, A.. Universita Tor Vergata; ItaliaFil: Cammilleri, D.. APC; FranciaFil: Cavaliere, F.. University of Milan; ItaliaFil: Chanial, P.. APC; FranciaFil: Etchegoyen, Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Tecnología en Detección y Astropartículas. Comisión Nacional de Energía Atómica. Instituto de Tecnología en Detección y Astropartículas. Universidad Nacional de San Martín. Instituto de Tecnología en Detección y Astropartículas; ArgentinaFil: Harari, Diego Dario. Comisión Nacional de Energía Atómica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Medina, Maria Clementina. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Argentino de Radioastronomía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Argentino de Radioastronomía; ArgentinaFil: Romero, Gustavo Esteban. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Argentino de Radioastronomía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Argentino de Radioastronomía; ArgentinaFil: Suarez, Federico. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Tecnología en Detección y Astropartículas. Comisión Nacional de Energía Atómica. Instituto de Tecnología en Detección y Astropartículas. Universidad Nacional de San Martín. Instituto de Tecnología en Detección y Astropartículas; ArgentinaThe European Physical Society Conference on High Energy PhysicsVeneciaItaliaEuropean Physical Societ

QUBIC instrument for CMB polarization measurements

Measurements of cosmic microwave background (CMB) polarization may reveal the presence of a background of gravitational waves produced during cosmic inflation, providing thus a test of inflationary models. The Q&U Bolometric Interferometer for Cosmology (QUBIC) is an experiment designed to measure the CMB polarization. It is based on the novel concept of bolometric interferometry, which combines the sensitivity of bolometric detectors with the properties of beam synthesis and control of calibration offered by interferometers. To modulate and extract the input polarized signal of the CMB, QUBIC exploits Stokes polarimetry based on a rotating half-wave plate (HWP). In this work, we illustrate the design of the QUBIC instrument, focusing on the polarization modulation system, and we present preliminary results of beam calibrations and the performance of the HWP rotator at 300 K

QUBIC: A Fizeau Interferometer Targeting Primordial B-Modes

Q and U Bolometric Interferometer for Cosmology (QUBIC) is a Fizeau interferometer sensitive to linear polarisation, to be deployed at the Antarctic station of Dome C. This experiment in its final configuration will be operated at 97, 150 and 220 GHz and is intended to target CMB primordial B-modes in a multipole window 20<ℓ<150. A sensitivity of r=0.05 (95 % CL) can be reached by the first module alone, after 2 years of operation. Here we review in particular its working principles, and we show how the QUBIC interferometric configuration can be considered equivalent to a pupil-plane filtered imaging system. In this context, we show how our instrument can be self-calibrated. Finally, we conclude by showing an overview of the first dual-band module (150/220 GHz), which will serve also as a demonstrator for the subsequent units, and review the technological choices we made for each subsystem, with particular emphasis on the detection system

Simulations and performance of the QUBIC optical beam combiner

QUBIC, the Q & U Bolometric Interferometer for Cosmology, is a novel ground-based instrument that aims to measure the extremely faint B-mode polarisation anisotropy of the cosmic microwave background at intermediate angular scales (multipoles o

Superconducting NbN Coplanar Switch Driven by DC Current for CMB Instruments

International audienc

Superconducting coplanar switch and phase shifter for CMB applications

International audienceThe next generations of cosmic microwave background (CMB) instruments will be dedicated to the detection and characterization of CMB B-modes. To measure this tiny signal, instruments need to control and minimize systematics. Signal modulation is one way to achieve such a control. A new generation of focal planes will include the entire detection chain. In this context, we present a superconducting coplanar switch driven by DC current. It consists of a superconducting microbridge which commutes between its on (superconducting) and off (normal metal) states, depending on the amplitude of the injected current compared to the critical current. If the current injected inside the bridge is lower than the critical current, the phase of the signal passing through the bridge is tunable. A first prototype of this component working as a switch and as a phase shifter at 10 GHz has been made. The principle, the setup, and the first measurements made at 4 K will be shown

LEKIDs as mm-Wave Polarisation Analysers: Fabrication, Test Bench and Early Results

International audienceWe have demonstrated in an earlier paper that LEKIDs can be used in a polarisation selective way in a filled array configuration. A polarised response can be achieved by means of thick Nb polarising grids lithographed on the rear side of a 300 microns silicon wafer, on which Al resonators have been previously patterned. In the most interesting scheme that we have investigated, a unit cell formed by 4 pixels (2 by 2) responds simultaneously to two orthogonal (cartesian) polarisation states. To assess the effectiveness of this detection scheme, we have fabricated a first generation of devices (9 small arrays, 20–25 pixels each, on a 4$^{\prime \prime }$ Silicon wafer) by using a double-sided mask aligner suitable for a precise positioning of the individual grids in correspondence of each resonator’s meander, for the different LEKID geometries. We describe here the realisation of these first devices. The construction of a dedicated polarimetric test bench is also described in this contribution, together with the first characterisation results. We consider this activity as a first and necessary step to evaluate the polarisation purity attainable with polarisation-sensitive pixels whose size is comparable to the wavelength. This is a fundamental information to drive further studies