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

Cavaliere, F.; Mennella, A.; Zannoni, M.; Battaglia, P.; Battistelli, E. S.; De Bernardis, P.; Burke, D.; D'Alessandro, G.; De Petris, M.; Franceschet, C.; Grandsire, L.; Hamilton, J. -Ch.; Maffei, B.; Manzan, B.; Marnieros, S.; Masi, S.; O'Sullivan, C.; Passerini, A.; Pezzotta, F.; Piat, M.; Tartari, A.; Torchinsky, S. A.; Vigan??, D.; Voisin, F.; Ade, P.; Alberro, J. G.; Almela, A.; Amico, G.; Arnaldi, L. H.; Auguste, D.; Aumont, J.; Azzoni, S.; Banfi, S.; Ba??, A.; B??lier, B.; Bennett, D.; Berg??, L.; Bernard, J. -Ph.; Bersanelli, M.; Bigot-Sazy, M. -A.; Bonaparte, J.; Bonis, J.; Bunn, E.; Buzi, D.; Chanial, P.; Chapron, C.; Charlassier, R.; Cobos Cerutti, A. C.; Columbro, F.; Coppolecchia, A.; De Gasperis, G.; De Leo, M.; Dheilly, S.; Duca, C.; Dumoulin, L.; Etchegoyen, A.; Fasciszewski, A.; Ferreyro, L. P.; Fracchia, D.; Gamboa Lerena, M. M.; Ganga, K. M.; Garc??a, B.; Redondo, M. E. Garc??a.; Gaspard, M.; Gayer, D.; Gervasi, M.; Giard, M.; Gilles, V.; Giraud-Heraud, Y.; G??mez Berisso, M.; Gonz??lez, M.; Gradziel, M.; Hampel, M. R.; Harari, D.; Henrot-Versill??, S.; Incardona, F.; Jules, E.; Kaplan, J.; Kristukat, C.; Lamagna, L.; Loucatos, S.; Louis, T.; Marty, W.; Mattei, A.; May, A.; Mcculloch, M.; Mele, L.; Melo, D.; Montier, L.; Mousset, L.; Mundo, L. M.; Murphy, J. A.; Murphy, J. D.; Nati, F.; Olivieri, E.; Oriol, C.; Paiella, A.; Pajot, F.; Pastoriza, H.; Pelosi, A.; Perbost, C.; Perciballi, M.; Piacentini, F.; Piccirillo, L.; Pisano, G.; Platino, M.; Polenta, G.; Pr??le, D.; Puddu, R.; Rambaud, D.; Rasztocky, E.; Ringegni, P.; Romero, G. E.; Salum, J. M.; Schillaci, A.; Sc??ccola, C. G.; Scully, S.; Spinelli, S.; Stankowiak, G.; Stolpovskiy, M.; Supanitsky, A. D.; Thermeau, J. -P.; Timbie, P.; Tomasi, M.; Tucker, C.; Tucker, G.; Vittorio, N.; Wicek, F.; Wright, M.; Zullo, A.

doi:10.1088/1475-7516/2022/04/040

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 consists of 64 back-to-back dual-band (150 GHz and 220 GHz) corrugated feed-horns interposed 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 waveguide between the back-to-back horns and are operated by miniaturized electromagnets. The measured electromagnetic performance of the feedhorns agrees with simulations. In particular we obtained a return loss around -20 dB up to 230 GHz and beam patterns in agreement with single-mode simulations down to -30 dB. The switches for this prototype were designed and built for the 150 GHz band. In this frequency range we find return and insertion losses consistent with expectations (< -25 dB and ∼-0.1 dB, respectively) and an isolation larger than 70 dB. In this paper 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.

QUBIC VII: The feedhorn-switch system of the technological demonstrator / Cavaliere, F., Mennella, A., Zannoni, M., Battaglia, P., Battistelli, E.S., de Bernardis, P., Burke, D., D'Alessandro, G., De Petris, M., Franceschet, C., Grandsire, L., Hamilton, J.-Ch., Maffei, B., Manzan, B., Marnieros, S., Masi, S., O'Sullivan, C., Passerini, A., Pezzotta, F., Piat, M., et al.. - In: JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS. - ISSN 1475-7516. - 2022:4(2022), p. 040. [10.1088/1475-7516/2022/04/040]