1. Optical design and modelling of the QUBIC instrument, a next-generation quasi-optical bolometric interferometer for cosmology
- Author
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A. Ghribi, L. Montier, D. Cammileri, D. Burke, L. Grandsire, J. Brossard, Peter T. Timbie, J. A. Murphy, Créidhe O'Sullivan, Giampaolo Pisano, N. Bleurvacq, J. C. Hamilton, P. Battaglia, J. Kaplan, Emory F. Bunn, G. Bordier, Marco Bersanelli, Alessandro Schillaci, Mario Zannoni, M. Giard, J.-Ph. Bernard, S. Scully, B. Bélier, J. Lande, O. Rigaut, T. Decourcelle, Giuseppe D'Alessandro, M.-A. Bigot-Sazy, A. Mennella, D. Buzi, A. Gault, Cristian Franceschet, M. Piat, O. Perdereau, D. Prêle, D. Bennet, Victor Haynes, L. Dumoulin, S. Banfi, J. Martino, F. Voisin, Lucio Piccirillo, D. Viganò, Sophie Henrot-Versille, M. W. Ng, Y. Giraud-Héraud, Massimo Gervasi, Andrei Korotkov, Marcin Gradziel, F. Piacentini, Maria Salatino, P. Chanial, Damien Rambaud, Jonathan Aumont, Simon J. Melhuish, A. Baù, N. Holtzer, M. De Petris, Mark McCulloch, M. Stolpovskiy, F. Del Torto, S. Marnieros, Bruno Maffei, P. de Bernardis, F. Pajot, Elia S. Battistelli, D. Gayer, Francesco Cavaliere, Gregory S. Tucker, L. Bergé, Alessandro Coppolecchia, A. Lowitz, M. Tristram, C. Perbost, B. Watson, R. Puddu, F. Couchot, D. Néel, A. Passerini, A. Tartari, C. Chapron, Silvia Masi, Holland, WS, Scully, S, Burke, D, O'Sullivan, C, Gayer, D, Gradziel, M, Murphy, J, De Petris, M, Buzi, D, Zannoni, M, Mennella, A, Gervasi, M, Tartari, A, Maffei, B, Aumont, J, Banfi, S, Battaglia, P, Battistelli, E, Bau', A, Bélier, B, Bennet, D, Bergé, L, Bernard, J, Bersanelli, M, Bigot Sazy, M, Bleurvacq, N, Bordier, G, Brossard, J, Bunn, E, Cammileri, D, Cavaliere, F, Chanial, P, Chapron, C, Coppolecchia, A, Couchot, F, D'Alessandro, G, De Bernardis, P, Decourcelle, T, Del Torto, F, Dumoulin, L, Franceschet, C, Gault, A, Ghribi, A, Giard, M, Giraud Héraud, Y, Grandsire, L, Hamilton, J, Haynes, V, Henrot Versillé, S, Holtzer, N, Kaplan, J, Korotkov, A, Lande, J, Lowitz, A, Marnieros, S, Martino, J, Masi, S, Mcculloch, M, Melhuish, S, Montier, L, Néel, D, Ng, M, Pajot, F, Passerini, A, Perbost, C, Perdereau, O, Piacentini, F, Piat, M, Piccirillo, L, Pisano, G, Prêle, D, Puddu, R, Rambaud, D, Rigaut, O, Salatino, M, Schillaci, A, Stolpovskiy, M, Timbie, P, Tristram, M, Tucker, G, Viganò, D, Voisin, F, and Watson, B
- Subjects
Bolometric interferometry ,QUBIC ,Aperture ,Cosmic microwave background ,Condensed Matter Physic ,Astrophysics::Cosmology and Extragalactic Astrophysics ,CMB ,01 natural sciences ,Cosmology ,law.invention ,010309 optics ,Telescope ,FIS/05 - ASTRONOMIA E ASTROFISICA ,symbols.namesake ,Optics ,law ,0103 physical sciences ,Astronomical interferometer ,Stokes parameters ,Electrical and Electronic Engineering ,Planck ,010303 astronomy & astrophysics ,Physics ,business.industry ,Electronic, Optical and Magnetic Material ,Astrophysics::Instrumentation and Methods for Astrophysics ,B-modes ,Electronic, Optical and Magnetic Materials ,Condensed Matter Physics ,Computer Science Applications1707 Computer Vision and Pattern Recognition ,Applied Mathematics ,Applied Mathematic ,Interferometry ,FIS/01 - FISICA SPERIMENTALE ,B-mode ,symbols ,business - Abstract
Big Bang cosmologies predict that the cosmic microwave background (CMB) contains faint temperature and polarisation anisotropies imprinted in the early universe. ESA's PLANCK satellite has already measured the temperature anisotropies1 in exquisite detail; the next ambitious step is to map the primordial polarisation signatures which are several orders of magnitude lower. Polarisation E-modes have been measured2 but the even-fainter primordial B-modes have so far eluded detection. Their magnitude is unknown but it is clear that a sensitive telescope with exceptional control over systematic errors will be required. QUBIC3 is a ground-based European experiment that aims to exploit the novel concept of bolometric interferometry in order to measure B-mode polarisation anisotropies in the CMB. Beams from an aperture array of corrugated horns will be combined to form a synthesised image of the sky Stokes parameters on two focal planes: one at 150 GHz the other at 220 GHz. In this paper we describe recent optical modelling of the QUBIC beam combiner, concentrating on modelling the instrument point-spread-function and its operation in the 220-GHz band. We show the effects of optical aberrations and truncation as successive components are added to the beam path. In the case of QUBIC, the aberrations introduced by off-axis mirrors are the dominant contributor. As the frequency of operation is increased, the aperture horns allow up to five hybrid modes to propagate and we illustrate how the beam pattern changes across the 25% bandwidth. Finally we describe modifications to the QUBIC optical design to be used in a technical demonstrator, currently being manufactured for testing in 2016.
- Published
- 2016