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arXiv · 2003.08949

Simons Observatory Microwave SQUID Multiplexing Readout -- Cryogenic RF Amplifier and Coaxial Chain Design

Mayuri Sathyanarayana Rao·Maximiliano Silva-Feaver·Aamir Ali·Kam Arnold·Peter Ashton·Bradley J. Dober·Cody J. Duell·Shannon M. Duff·Nicholas Galitzki·Erin Healy·Shawn Henderson·Shuay-Pwu Patty Ho·Jonathan Hoh·Anna M. Kofman·Akito Kusaka·Adrian T. Lee·Aashrita Mangu·Justin Mathewson·Philip Mauskopf·Heather McCarrick·Jenna Moore·Michael D. Niemack·Christopher Raum·Maria Salatino·Trevor Sasse·Joseph Seibert·Sara M. Simon·Suzanne Staggs·Jason R. Stevens·Grant Teply·Robert Thornton·Joel Ullom·Eve M. Vavagiakis·Benjamin Westbrook·Zhilei Xu·Ningfeng Zhu
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Abstract

The Simons Observatory (SO) is an upcoming polarization-sensitive Cosmic Microwave Background (CMB) experiment on the Cerro Toco Plateau (Chile) with large overlap with other optical and infrared surveys (e.g., DESI, LSST, HSC). To enable the readout of \bigO(10,000) detectors in each of the four telescopes of SO, we will employ the microwave SQUID multiplexing technology. With a targeted multiplexing factor of \bigO{(1,000)}, microwave SQUID multiplexing has never been deployed on the scale needed for SO. Here we present the design of the cryogenic coaxial cable and RF component chain that connects room temperature readout electronics to superconducting resonators that are coupled to Transition Edge Sensor bolometers operating at sub-Kelvin temperatures. We describe design considerations including cryogenic RF component selection, system linearity, noise, and thermal power dissipation.

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Mayuri Sathyanarayana Rao, Maximiliano Silva-Feaver, Aamir Ali, Kam Arnold, Peter Ashton, Bradley J. Dober, Cody J. Duell, Shannon M. Duff, Nicholas Galitzki, Erin Healy, Shawn Henderson, Shuay-Pwu Patty Ho, Jonathan Hoh, Anna M. Kofman, Akito Kusaka, Adrian T. Lee, Aashrita Mangu, Justin Mathewson, Philip Mauskopf, Heather McCarrick, Jenna Moore, Michael D. Niemack, Christopher Raum, Maria Salatino, Trevor Sasse, Joseph Seibert, Sara M. Simon, Suzanne Staggs, Jason R. Stevens, Grant Teply, Robert Thornton, Joel Ullom, Eve M. Vavagiakis, Benjamin Westbrook, Zhilei Xu, Ningfeng Zhu. 2020-03-19. Simons Observatory Microwave SQUID Multiplexing Readout -- Cryogenic RF Amplifier and Coaxial Chain Design. https://doi.org/10.1007/s10909-020-02429-y

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