We demonstrate that polarimetric interferometry can be used to extract precise spatial information about compact polarized flares of Sgr A*. We show that, for a faint dynamical component, a single interferometric baseline suffices to determine both its polarization and projected displacement from the quiescent intensity centroid. A second baseline enables two-dimensional reconstruction of the displacement, and additional baselines can self-calibrate using the flare, enhancing synthesis imaging of the quiescent emission. We apply this technique to simulated 1.3?mm wavelength observations of a "hot spot" embedded in a radiatively inefficient accretion disk around Sgr A*. Our results indicate that, even with current sensitivities, polarimetric interferometry with the Event Horizon Telescope can achieve ~5 μas relative astrometry of compact flaring structures near Sgr A* on timescales of minutes.
展开▼
机译：我们证明了偏振干涉法可用于提取有关Sgr A *的紧凑偏振光斑的精确空间信息。我们表明，对于微弱的动力学分量，单个干涉基线足以确定其极化和从静态强度重心投影的位移。第二个基线可以对位移进行二维重建，其他基线可以使用耀斑进行自我校准，从而增强了静态发射的合成成像。我们将此技术应用于模拟在Sgr A *周围辐射效率低的吸积盘中嵌入的“热点”的1.3？mm波长观测值。我们的结果表明，即使在电流敏感的情况下，Event Horizon望远镜的偏振干涉测量法也能在几分钟的时间内将Sgr A *附近的紧凑扩口结构的相对天文测量值提高至约5μs。
展开▼
