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

ZANNONI, M.; DE BERNARDIS, P.; DE PETRIS, M.; HAMILTON, J.-CH.; MARNIEROS, S.; PASSERINI, A.; TARTARI, A.; VOISIN, F.; ALMELA, A.; AUGUSTE, D.; BANFI, S.; BENNETT, D.; BERSANELLI, M.; BONIS, J.; CHANIAL, P.; COBOS CERUTTI, A.C.; DE GASPERIS, G.; DUCA, C.; FASCISZEWSKI, A.; GAMBOA LERENA, M.M.; GARCÍA REDONDO, M.E.; GERVASI, M.; GIRAUD-HERAUD, Y.; GRADZIEL, M.; HENROT-VERSILLÉ, S.; KAPLAN, J.; LOUCATOS, S.; MATTEI, A.; MELE, L.; MOUSSET, L.; MURPHY, J.D.; ORIOL, C.; PASTORIZA, H.; PERCIBALLI, M.; PISANO, G.; PRÊLE, D.; RASZTOCKY, E.; SALUM, J.M.; SCULLY, S.; STOLPOVSKIY, M.; TIMBIE, P.; TUCKER, G.; WRIGHT, M.; CAVALIERE, F.; BATTAGLIA, P.; BURKE, D.; FRANCESCHET, C.; MAFFEI, B.; MASI, S.; PEZZOTTA, F.; TORCHINSKY, S.A.; ADE, P.; AMICO, G.; AUMONT, J.; BAÙ, A.; BERGÉ, L.; BIGOT-SAZY, M.-A.; BUNN, E.; CHAPRON, C.; COLUMBRO, F.; DE LEO, M.; DUMOULIN, L.; FERREYRO, L.P.; GANGA, K.M.; GASPARD, M.; GIARD, M.; GÓMEZ BERISSO, M.; HAMPEL, M.R.; INCARDONA, F.; MENNELLA, A.; KRISTUKAT, C.; BATTISTELLI, E.S.; LOUIS, T.; D

JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS

IOP PUBLISHING LTD

Lugar: Londres; Año: 2022 vol. 2022

1475-7516

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.