BICEP Array: 150 GHz detector module development

A. Schillaci , P.A.R. Ade , Z. Ahmed , M. Amiri , D. Barkats , R. Basu Thakur , C.A. Bischoff , D. Beck , J.J. Bock , V. Buza , J. Cheshire , J. Connors , J. Cornelison , M. Crumrine , A. Cukierman , E. Denison , M. Dierickx , L. Duband (1) , M. Eiben , S. Fatigoni , J.P. Filippini , C. Giannakopoulos , N. Goeckner-Wald , D. Goldfinger , J.A. Grayson , P. Grimes , G. Hall , G. Halal , M. Halpern , E. Hand , S. Harrison , S. Henderson , S.R. Hildebrandt , G.C. Hilton , J. Hubmayr , H. Hui , K.D. Irwin , J. Kang , K.S. Karkare , S. Kefeli , J.M. Kovac , C.L. Kuo , K. Lau , E.M. Leitch , A. Lennox , K.G. Megerian , O.Y. Miller , L. Minutolo , L. Moncelsi , Y. Nakato , T. Namikawa , H.T. Nguyen , R. O'Brient , S. Palladino , M. Petroff , N. Precup , T. Prouve (1) , C. Pryke , B. Racine , C.D. Reintsema , B.L. Schmitt , B. Singari , A. Soliman , T. St. Germaine , B. Steinbach , R.V. Sudiwala , K.L. Thompson , C. Tucker , A.D. Turner , C. Umilta , C. Verges , A.G. Vieregg , A. Wandui , A.C. Weber , D.V. Wiebe , J. Willmert , W.L.K. Wu , E. Yang , K.W. Yoon , E. Young , C. Yu , L. Zeng , C. Zhang , S. Zhang

1 LCCS - Laboratoire des Cryoréfrigérateurs et Cryogénie Spatiale

The BICEP/Keck Collaboration is currently leading the quest to the highest sensitivity measurements of the polarized CMB anisotropies on degree scale with a series of cryogenic telescopes, of which BICEP Array is the latest Stage-3 upgrade with a total of $\sim32,000$ detectors. The instrument comprises 4 receivers spanning 30 to 270 GHz, with the low-frequency 30/40 GHz deployed to the South Pole Station in late 2019. The full complement of receivers is forecast to set the most stringent constraints on the tensor to scalar ratio $r$. Building on these advances, the overarching small-aperture telescope concept is already being used as the reference for further Stage-4 experiment design. In this paper I will present the development of the BICEP Array 150 GHz detector module and its fabrication requirements, with highlights on the high-density time division multiplexing (TDM) design of the cryogenic circuit boards. The low-impedance wiring required between the detectors and the first-stage SQUID amplifiers is crucial to maintain a stiff voltage bias on the detectors. A novel multi-layer FR4 Printed Circuit Board (PCB) with superconducting traces, capable of reading out up to 648 detectors, is presented along with its validation tests. I will also describe an ultra-high density TDM detector module we developed for a CMB-S4-like experiment that allows up to 1,920 detectors to be read out. TDM has been chosen as the detector readout technology for the Cosmic Microwave Background Stage-4 (CMB-S4) experiment based on its proven low-noise performance, predictable costs and overall maturity of the architecture. The heritage for TDM is rooted in mm- and submm-wave experiments dating back 20 years and has since evolved to support a multiplexing factor of 64x in Stage-3 experiments.

Mots clés: detector: cryogenics; cryogenics: design; cosmic background radiation: anisotropy; BICEP; buildings; upgrade; superconductivity; sensitivity; density; amplifier; readout; pole; costs; performance; fabrication

Domaines: Instrumentations et Détecteurs [physics.ins-det]; Astrophysique [astro-ph]

A. Schillaci, P.A.R. Ade, Z. Ahmed, M. Amiri, D. Barkats, et al.. BICEP Array: 150 GHz detector module development. J.Low Temp.Phys., 2023, 213 (5-6), pp.317-326. ⟨10.1007/s10909-023-03005-w⟩. ⟨hal-03483604⟩