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The microwave SQUID multiplexer (μ MUX) is a high channel-count multiplexer that, when coupled to low-temperature detectors such as Transition Edge Sensor (TES) Bolometers, has applications across astronomy and physics. Our primary application is for the Simons Observatory, an array of CMB polarimeters utilizing over 70,000 μ MUX readout channels, located in the Atacama Desert. To facilitate the delivery of high-quality multiplexers to the project, we have developed a high-throughput microwave SQUID screening measurement system, capable of measuring microwave devices operating over the frequency range of 4–8 GHz. Here, we present the hardware design comprised of a cryogen-free 100 mK 2-stage Adiabatic Demagnetization Refrigerator (ADR) cryostat, microwave packages which hold μ MUX chips, and the microwave readout chain necessary to do these measurements. In addition, we describe the screening protocols and show example results. [ABSTRACT FROM AUTHOR]

• The EDIPO test facility is undergoing a major upgrade. • The design, integration and operation of the new cryostat is discussed. • The total thermal budget of the cryostat is computed analytically. • The helium vessel has been designed according to EN 13445 and manufactured. • Structural simulations are compared with experimental pressure tests. A major upgrade of the European DIPOle (EDIPO) test facility, which will allow the testing of superconducting samples both for fusion and for high-energy physics applications, is taking place at the Swiss Plasma Center. With a target background field of 15 T, the new magnet design requires a large engineering current density and thus an accelerator-like magnet cooled by a saturated helium bath is foreseen. Therefore, a helium vessel has been designed and procured. In this work, we present recent advances in the design and manufacturing activities of the EDIPO 2 cryostat. First, we provide an analytical estimation of the thermal budget at the temperature levels of interest. Then, we describe the design and manufacturing of the helium vessel, according to relevant norms. Finite-element numerical simulations are employed both to refine the design and to provide a comparison with the experimental pressure tests. [ABSTRACT FROM AUTHOR]

In the framework of the FAIR [1] project, the PAX collaboration has suggested new experiments using polarized antiprotons [2]. The central physics issue is now to study the polarization build-up by spin filtering of antiprotons via multiple passages through an internal polarized gas target. The goals for spin-filtering experiments with protons at COSY are to test our understanding of the spin-filtering processes and to commission the setup for the AD experiments with antiprotons at the AD (CERN). Spin-filtering experiments with antiprotons at the AD will allow us to determine the total spin-dependent transversal and longitudinal cross sections. The low-beta section at COSY is composed of two superconducting quadrupole magnets on each side of the target, while at the AD, we will use three quadrupoles on each side. Technical problems and details of the superconducting quadrupoles with their respective cryogenics will be discussed. A flexible cryogenic system fitting at COSY and AD ring characterized by a low liquid helium consumption will be discussed. The status of the quadrupoles will be reported as well. [ABSTRACT FROM AUTHOR]