罗曼日冕仪社区参与计划：利用天基源校准穆勒矩阵的策略
The Roman Coronagraph Community Participation Program: calibration strategy for the Mueller matrix using on-sky sources
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中文总结 AI 辅助
该研究针对罗曼空间望远镜日冕仪的穆勒矩阵校准需求，构建候选星表并选取校准星，通过模拟估算线性偏振度重建精度，推进基于corgisim和corgiDRP的端到端测试。
中文摘要 AI 辅助
南希·格蕾丝·罗曼空间望远镜日冕仪将提供对星周盘和系外行星系统的天基偏振观测。准确重建线性偏振度（LPF）需要利用偏振和弱偏振标准星校准仪器的穆勒矩阵。我们结合已发表的光学偏振测量数据与盖亚DR3天体测量和测光数据构建了候选星表，并为日冕仪校准观测和使用中性密度滤光片的观测分别选取了样本。我们用1.5米加那塔望远镜上的HONIR获取了18个暗弱候选星的前驱VRI波段偏振测量数据，采用塞科夫斯基定律对其归一化斯托克斯参数的波长依赖关系建模，以预测它们在CGI波段1和4中的偏振特性，并为两种校准场景各选取了3个校准星。随后，我们通过蒙特卡洛模拟估算了可实现的LPF重建精度，该模拟包含校准星光偏振特性的不确定性、测光噪声以及探测器响应残余误差，还模拟了抖动观测配置以减少校准星间的探测器响应差分误差。当前估算显示LPF重建误差处于百分之几的水平，将弱偏振校准星当作非偏振星处理会产生小的偏差。最后，我们介绍了使用corgisim和corgiDRP进行端到端测试的进展，包括成功处理从1级到2b级的模拟数据集。
英文摘要
The Nancy Grace Roman Space Telescope Coronagraph Instrument will provide space-based polarimetric observations of circumstellar disks and exoplanetary systems. Accurate reconstruction of the linear polarization fraction requires calibration of the instrumental Mueller matrix using polarized and weakly polarized standard stars. We constructed a candidate catalog by combining published optical polarimetry with Gaia DR3 astrometry and photometry and selected separate samples for coronagraphic calibration observations and observations using a neutral-density filter. Precursor $VRI$-band polarimetry of 18 faint candidates was obtained with HONIR on the 1.5-m Kanata telescope. The wavelength dependence of their normalized Stokes parameters was modeled using the Serkowski law to predict their polarization properties in \cgi\ Bands~1 and 4, and 2 sets of 3 calibrators were selected for the 2 calibration scenarios. We then estimated the achievable LPF reconstruction accuracy using Monte Carlo simulations that include uncertainties in the calibrator polarization properties, photometric noise, and residual detector-response errors. A dithered observing configuration was also simulated to reduce differential detector-response errors among the calibrators. The current estimates indicate LPF reconstruction errors at the few-percentage-point level, with a small bias arising from treating a weakly polarized calibrator as unpolarized. Finally, we present progress toward an end-to-end test using \texttt{corgisim} and \texttt{corgiDRP}, including successful processing of simulated datasets from Level~1 through Level~2b.
