AI 中文总结
该研究在正则化最大似然框架内，提出用最优传输距离作为正则化项，改进射电干涉数据的动态视频重建，经EHT对SgrA*的VLBI观测测试，其动态重建效果优于无该正则化的方法。
AI 中文摘要
我们提出了一种新的技术，用于利用最优传输（OT）距离作为正则化项，在正则化最大似然（RML）框架内对射电干涉数据进行动态视频重建。与RML及相关基于先验的方法中其他常用正则化项相比，OT距离能更自然地捕捉包括物理运动在内的信息，并促进动力学的连贯性。这一特性使OT正则化特别适合对分钟时间尺度上的天体物理现象进行动态成像。我们对银河系中心超大质量黑洞人马座A*（SgrA*）的甚长基线干涉测量（VLBI）观测进行了一系列测试，这些观测由事件视界望远镜（EHT）完成，采用了几何模型和广义相对论磁流体动力学模型。我们证明，添加OT正则化项后，与未添加的情况相比，动态重建有显著改进，表现为轨道运动的恢复效果更好，动态互相关指标更高。OT理论在各领域的持续发展、对EHT网络的拟议扩展，以及其对其他VLBI网络的广泛适用性，都表明用于动态射电干涉重建的OT正则化将在未来得到持续应用和改进。
英文摘要
We propose a new technique for dynamic video reconstruction of radio interferometric data using the optimal transport (OT) distance as a regularizer within the regularized maximum likelihood (RML) framework. Compared to other commonly used regularization terms in RML and related prior-based approaches, the OT distance more naturally captures information including physical motion and promotes coherent dynamics. This property makes the OT regularization particularly suitable for dynamic imaging of astrophysical phenomena on minute timescales. We perform a series of tests on simulated very long baseline interferometric (VLBI) observations of Sagittarius A$^\ast$ (SgrA*), the supermassive black hole at the Galactic Center, with the Event Horizon Telescope (EHT), using both geometric and general relativistic magnetohydrodynamic models. We demonstrate that adding an OT regularization term yields significant improvements in dynamic reconstructions compared to those without it, as quantified by better recovery of orbital motion and higher dynamic cross-correlation metrics. Continued developments in OT theory across various fields, proposed extensions to the EHT network, and broad applicability to other VLBI networks make it so that OT regularization for dynamic radio interferometric reconstructions will continue to be utilized and improved in the future.
Comments13 pages, 7 figures, submitted to A&A
