Thermal and Electrical Properties of Prototype Readout Components for CMB-S4

Wilber Dominguez; Darcy R. Barron; Zeeshan Ahmed; Amy N. Bender; Sandra Diez; Malcolm Durkin; Tristan A. Eggenberger; Gunther Haller; Shawn W. Henderson; Katherine Hewey; Johannes Hubmayr; Christopher Rooney; Robinjeet Singh; Michael Vissers

arXiv · 2511.02173

Thermal and Electrical Properties of Prototype Readout Components for CMB-S4

Wilber Dominguez·Darcy R. Barron·Zeeshan Ahmed·Amy N. Bender·Sandra Diez·Malcolm Durkin·Tristan A. Eggenberger·Gunther Haller·Shawn W. Henderson·Katherine Hewey·Johannes Hubmayr·Christopher Rooney·Robinjeet Singh·Michael Vissers

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Abstract

CMB-S4 is the fourth-generation ground-based cosmic microwave background project, designed to probe the early universe and cosmic inflation. CMB-S4 would achieve its science goals in part by dramatically increasing the number of transition edge sensor (TES) bolometer detectors on the sky. The detector readout system for CMB-S4 is time-division multiplexing (TDM) with a two-stage Superconducting Quantum Interference Device (SQUID) system. To accommodate the large increase in detectors, the size of our camera increases, placing physical constraints on the readout, its wiring, and its power dissipation. Therefore, to optimize readout performance, we need to balance competing design considerations such as thermal load and bandwidth. We present results characterizing the thermal and electrical performance of prototype components, including wiring and SQUID arrays for CMB-S4, and discuss the impact on overall system performance.

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Wilber Dominguez, Darcy R. Barron, Zeeshan Ahmed, Amy N. Bender, Sandra Diez, Malcolm Durkin, Tristan A. Eggenberger, Gunther Haller, Shawn W. Henderson, Katherine Hewey, Johannes Hubmayr, Christopher Rooney, Robinjeet Singh, Michael Vissers. 2025-11-04. Thermal and Electrical Properties of Prototype Readout Components for CMB-S4. https://arxiv.org/abs/2511.02173

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