标题： 西蒙斯天文台：从宇宙学中微波频率复用的首次大规模部署研究射频传输线中的相位漂移 显示英文标题

标题： The Simons Observatory: Studies of Phase Drift in RF Transmission Lines from the First Large-Scale Deployment of Microwave Frequency Multiplexing for Cosmology

摘要： 实现西蒙斯天文台这一最先进的宇宙微波背景（CMB）实验的科学目标，需要部署数以万计的超导辐射计。在保持低温条件的同时，从天文台的67,000多个过渡边缘传感器（TES）探测器读取数据，需要一种有效的多路复用方案。SLAC微谐振器射频（SMuRF）电子设备已被开发出来，为高密度微波频率多路复用读出系统提供温暖电子设备，该系统已被证明可以实现约1,000倍的多路复用因子。SMuRF最近已部署到位于智利阿塔卡马沙漠Cerro Toco山顶5,200米处的西蒙斯天文台。由于SMuRF系统暴露在沙漠的日温变化中，射频传输线中的相位漂移可能会引入系统信号污染。我们研究了西蒙斯天文台6米大孔径望远镜的室温射频线路中的相位漂移，该望远镜目前是TES微波频率多路复用技术的最大部署。我们表明这些相位漂移的时间尺度明显长于天空扫描时间，并且它们对在轨过渡探测器噪声的贡献在读出噪声预算范围内。 显示英文摘要

摘要： Fulfilling the science goals of the Simons Observatory, a state-of-the-art cosmic microwave background (CMB) experiment, has required deploying tens of thousands of superconducting bolometers. Reading out data from the observatory's more than 67,000 transition-edge sensor (TES) detectors while maintaining cryogenic conditions requires an effective multiplexing scheme. The SLAC microresonator radio frequency (SMuRF) electronics have been developed to provide the warm electronics for a high-density microwave frequency multiplexing readout system, and this system has been shown to achieve multiplexing factors on the order of 1,000. SMuRF has recently been deployed to the Simons Observatory, which is located at 5,200 m on Cerro Toco in Chile's Atacama Desert. As the SMuRF system is exposed to the desert's diurnal temperature swings, resulting phase drift in RF transmission lines may introduce a systematic signal contamination. We present studies of phase drift in the room-temperature RF lines of the Simons Observatory's 6 m large-aperture telescope, which hosts the largest deployment to date of TES microwave frequency multiplexing to a single telescope. We show that these phase drifts occur on time scales which are significantly longer than sky scanning, and that their contribution to on-sky in-transition detector noise is within the readout noise budget.