标题： 地面鸟CMB偏振望远镜的全套探测器调试 显示英文标题

标题： Commissioning the CMB polarization telescope GroundBIRD with the full set of detectors

摘要： GroundBIRD是一项基于地面的宇宙微波背景（CMB）实验，旨在通过西班牙特内里费岛的泰德天文台观测大尺度角（$\ell > 6$）上的偏振模式。我们的主要科学目标是精确测量宇宙再电离时期的光学深度（$\tau$，$\sigma(\tau) \sim 0.01$），以验证前人实验中的系统误差。GroundBIRD在北半球观测广阔天空区域（$\sim 40\%$为全天的一小部分），同时以每分钟高达20转的速度持续旋转望远镜，以克服大气辐射波动的影响。 我们采用了NbTiN/Al混合微波超导动量检测器（MKIDs）作为焦平面探测器。我们观测两个频率带，中心频率分别为145 GHz和220 GHz。145 GHz频带捕捉了CMB光谱的峰值频率，而220 GHz频带有助于准确去除银河系星际尘埃热发射的污染。MKID阵列（145 GHz有138个MKIDs，220 GHz有23个MKIDs）经过设计和优化，以最小化双态系统噪声的干扰并最大化灵敏度。在实验室完成性能验证测试后，MKID阵列已于2023年5月成功安装。GroundBIRD现已升级为使用完整的MKID阵列，并开始进行科学观测。望远镜实现了自动化，因此所有观测均远程进行。包括极化响应测试和木星及月球观测在内的初步验证已成功完成。我们现在正在进行科学观测。 显示英文摘要

摘要： GroundBIRD is a ground-based cosmic microwave background (CMB) experiment for observing the polarization pattern imprinted on large angular scales ($\ell > 6$ ) from the Teide Observatory in Tenerife, Spain. Our primary scientific objective is a precise measurement of the optical depth $\tau$ ($\sigma(\tau) \sim 0.01$) to the reionization epoch of the Universe to cross-check systematic effects in the measurements made by previous experiments. GroundBIRD observes a wide sky area in the Northern Hemisphere ($\sim 40\%$ of the full sky) while continuously rotating the telescope at a high speed of up to 20 rotations per minute (rpm) to overcome the fluctuations of atmospheric radiation. We have adopted the NbTiN/Al hybrid microwave kinetic inductance detectors (MKIDs) as focal plane detectors. We observe two frequency bands centered at 145 GHz and 220 GHz. The 145 GHz band picks up the peak frequency of the CMB spectrum. The 220 GHz band helps accurate removal of the contamination of thermal emission from the Galactic interstellar dust. The MKID arrays (138 MKIDs for 145GHz and 23 MKIDs for 220GHz) were designed and optimized so as to minimize the contamination of the two-level-system noise and maximize the sensitivity. The MKID arrays were successfully installed in May 2023 after the performance verification tests were performed at a laboratory. GroundBIRD has been upgraded to use the full MKID arrays, and scientific observations are now underway. The telescope is automated, so that all observations are performed remotely. Initial validations, including polarization response tests and observations of Jupiter and the moon, have been completed successfully. We are now running scientific observations.