Microwave SQUID Multiplexing and Cryogenics

通过对~(163)Ho电子俘获光谱的量热测量来研究电子中微子的质量，需要使用基于MMC的大型探测器阵列。在研究单位“ECHO”的第一个资助阶段内，我们开发了一种可扩展的多路复用技术，以实现这些大型探测器阵列的读出。本项目的目标是使用这种多路复用技术来实现ECHO-100K的读出系统，该系统将使用大约6000个单独的探测器来调查2 eV/c2水平上的电子中微子质量。该读出系统的开发、实现和运行需要多路复用器设备的设计、制造和测试，以及将它们集成到将与WG2和WG4密切合作开发的整体探测器设置中。此外，我们将安装和调试低温微波装置，以及超导同轴电缆、HEMT放大器和低温循环器等设备。另一项相当重要的任务是委托基于软件无线电的室温读出电子设备来操作实际的多路复用器设备。该项目还旨在为未来进行更大的基于163Ho的实验铺平道路。为此，我们将开展一项专门的研发计划，以探索混合多路复用技术的适用性，降低读出系统的噪声，并开发新的超导微波器件，以提高整个读出系统的成本效益。

The investigation of the electron neutrino mass by means of the calorimetric measurement of the electron capture spectrum of 163Ho requires the operation of large MMC based detector arrays. Within the first funding phase of the Research Unit "ECHo", we have developed a scalable multiplexing technique for realizing the readout of these large detector arrays. The present project aims to use this multiplexing technique to implement a readout system for ECHo-100k that will use about 6000 individual detectors to investigate the electron neutrino mass on a 2 eV/c2 level. The development, realization and operation of this readout system requires the design, fabrication and testing of the multiplexer devices as well as the integration of them into the overall detector setup which will be developed in close collaboration with WG2 and WG4. In addition, we will install and commission the cryogenic microwave setups consisting among other devices of the superconducting coaxial cables, the HEMT amplifier as well as the cryogenic circulator. Another quite important task is the commission of the software defined radio based room-temperature readout electronics which operates the actual multiplexer devices. The project further aims to pave the way for performing an even larger 163Ho based experiment in the future. For this, we will perform a dedicated R&D program to explore the suitability of hybrid multiplexing techniques, to lower the noise of the readout system as well as to develop new superconducting microwave devices to increase the cost efficiency of the overall readout system.