AI 中文总结
介绍蜻蜓偏振仪，利用蜻蜓长焦阵列架构，能在约5平方度视场同时测四个偏振方向。集成偏振器等并经实验室表征及在轨调试，9月实现首次偏振光测量，可用于磁场测绘等多科学目标。
AI 中文摘要
我们介绍了蜻蜓偏振仪，这是一种在蜻蜓长焦阵列上实现的宽视场光学线性偏振测量功能。蜻蜓偏振仪利用蜻蜓的模块化多镜头架构，在约5平方度的视场中，通过44个偏振透镜 - 探测器单元同时获取四个线性偏振方向（0°、45°、90°和135°）的测量值，另外四个单元用作非偏振参考通道。我们描述了此功能实现的广泛科学目标，包括磁场测绘和层析成像、尘埃颗粒特性、宇宙微波背景前景表征以及弥漫星际云的三维结构。我们将佳能偏振器和巴德 - 斯隆r'带通滤波器集成到佳能镜头的插入式滤光片支架中，并进行了一个三相实验室表征程序，以选择最佳偏振组件，测量对比度和传输效率，并以低于一度的重复性确定并标记每个偏振器的传输轴。对所有44个已部署偏振器的实验室测量得出，在r'波段中，平均噪声扣除对比度为1228±104，单偏振器传输效率约为33％。包括暮光平场表征和暮光天空偏振测量在内的在轨调试，确认了各偏振组的通量稳定性，并成功恢复了预期的瑞利散射信号。蜻蜓偏振仪于2025年9月实现了首次偏振光测量。
英文摘要
We present DragonflyPol, a wide-field optical linear polarimetry capability implemented on the Dragonfly Telephoto Array. DragonflyPol leverages Dragonfly's modular, multi-lens architecture to obtain simultaneous measurements in four linear polarization orientations ($0^\circ$, $45^\circ$, $90^\circ$, and $135^\circ$) across a $\sim5\,deg^2$ field of view, distributed across 44 polarized lens--detector units. Four additional units serve as unpolarized reference channels. We describe a broad range of science goals enabled by this capability, including magnetic field mapping and tomography, dust grain properties, CMB foreground characterization, and the three-dimensional structure of diffuse interstellar clouds. We integrate Canon polarizers and Baader Sloan $r'$ bandpass filters into the drop-in filter holders of the Canon lenses, and conduct a three-phase laboratory characterization program to select optimal polarimetric components, measure contrast ratios and transmission efficiencies, and determine and mark the transmission axis of each polarizer with sub-degree repeatability. Laboratory measurements across all 44 deployed polarizers yield a mean noise-subtracted contrast ratio of $1228 \pm 104$ and a single-polarizer transmission efficiency of $\sim$33\% in the $r'$ band. On-sky commissioning, including twilight flat-field characterization and twilight-sky polarization measurements, confirms throughput stability across polarization groups and successful recovery of the expected Rayleigh scattering signal. DragonflyPol achieved first polarimetric light in September 2025.
Comments17 pages, 11 Figures, submitted to PASP
