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arXiv · 2008.12721

QUBIC VII: The feedhorn-switch system of the technological demonstrator

Abstract

We present the design, manufacturing and performance of the horn-switch system developed for the technological demonstrator of QUBIC (the $Q$\&$U$ Bolometric Interferometer for Cosmology). This system is constituted of 64 back-to-back dual-band (150\,GHz and 220\,GHz) corrugated feed-horns interspersed with mechanical switches used to select desired baselines during the instrument self-calibration. We manufactured the horns in aluminum platelets milled by photo-chemical etching and mechanically tightened with screws. The switches are based on steel blades that open and close the wave-guide between the back-to-back horns and are operated by miniaturized electromagnets. We also show the current development status of the feedhorn-switch system for the QUBIC full instrument, based on an array of 400 horn-switch assemblies.

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F. Cavaliere, A. Mennella, M. Zannoni, P. Battaglia, E. S. Battistelli, D. Burke, G. D'Alessandro, P. de Bernardis, M. De Petris, C. Franceschet, L. Grandsire, J. -Ch. Hamilton, B. Maffei, E. Manzan, S. Marnieros, S. Masi, C. O'Sullivan, A. Passerini, F. Pezzotta, M. Piat, A. Tartari, S. A. Torchinsky, D. Viganò, F. Voisin, P. Ade, J. G. Alberro, A. Almela, G. Amico, L. H. Arnaldi, D. Auguste, J. Aumont, S. Azzoni, B. Bélier, A. Baù, S. Banfi, D. Bennett, L. Bergé, J. -Ph. Bernard, M. Bersanelli, M. -A. Bigot-Sazy, J. Bonaparte, J. Bonis, E. Bunn, D. Buzi, P. Chanial, C. Chapron, R. Charlassier, A. C. Cobos Cerutti, F. Columbro, A. Coppolecchia, G. De Gasperis, M. De Leo, S. Dheilly, C. Duca, L. Dumoulin, A. Etchegoyen, A. Fasciszewski, L. P. Ferreyro, D. Fracchia, M. Gómez Berisso, M. M. Gamboa Lerena, K. M. Ganga, B. García, M. E. García Redondo, M. Gaspard, D. Gayer, M. Gervasi, M. Giard, V. Gilles, Y. Giraud-Heraud, M. González, M. Gradziel, M. R. Hampel, D. Harari, S. Henrot-Versillé, F. Incardona, E. Jules, J. Kaplan, C. Kristukat, L. Lamagna, S. Loucatos, T. Louis, W. Marty, A. Mattei, A. May, M. McCulloch, L. Mele, D. Melo, L. Montier, L. Mousset, L. M. Mundo, J. A. Murphy, J. D. Murphy, F. Nati, E. Olivieri, C. Oriol, E. Pagana, A. Paiella, F. Pajot, H. Pastoriza. 2020-08-28. QUBIC VII: The feedhorn-switch system of the technological demonstrator. https://doi.org/10.1088/1475-7516/2022/04/040

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