发表机构
School of Physics and Astronomy, Beijing Normal University; School of Physics, Peking University; Key Laboratory of Multiscale Spin Physics (Beijing Normal University), Ministry of Education; School of Physical Science and Technology, Ningbo University（北京师范大学物理与天文学院; 北京大学物理学院; 教育部多尺度自旋物理重点实验室（北京师范大学）; 宁波大学物理科学与技术学院）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
CoportSL通过贡献约束混合慢光框架，在保证高精度（差异低于4e-3）的同时大幅减少内存和计算需求，实现时变全斯托克斯GRMHD成像。
AI 中文摘要
快光近似忽略了沿光线传播的流体演化，而慢光建模对于恢复真实的磁流体动力学状态不可或缺。然而，对扩展的广义相对论磁流体动力学（GRMHD）源进行完整的慢光辐射转移需要同时访问大量流体快照，且内存占用巨大。我们提出CoportSL，这是首个面向时变全斯托克斯成像的贡献约束混合慢光框架。它利用发射、吸收和法拉第贡献来识别必须保留流体演化的区域，在其他区域应用快光，并且仅加载覆盖相关延迟的快照。使用类似M87*的磁 Arrested 盘GRMHD数据进行的测试表明，基于贡献的区域和基于延迟的快照限制各自使归一化全图像斯托克斯差异相对于相应的完整计算保持在$4\ imes10^{-3}$以下。在此精度下，CoportSL在近地平线和喷流图像中分别减少了75.3%和44.7%的快照层；其每帧慢光转移时间与快光相当。对于这两种配置，源代码估算将主要数据结构的容量分别定为固定公共ipole版本的255-657 GiB和CoportSL的20.2-37.3 GiB，使两种配置都处于工作站级内存范围内。快慢光比较进一步显示近地平线变率高度一致，而喷流变率遵循相似的整体趋势，但在局部峰值和幅度上存在差异；在两种情况下，快光都遗漏了大量全斯托克斯空间结构。随着下一代事件视界望远镜（ngEHT）向动态成像和空间分辨偏振测量推进，CoportSL为在扩展黑洞系统中建模全斯托克斯有限光传播时间特征提供了一种计算上实用的方法。
英文摘要
Fast-light approximations neglect fluid evolution along rays, whereas slow-light modeling is indispensable for recovering the true magnetohydrodynamic state. However, full slow-light radiative transfer for extended general relativistic magnetohydrodynamic (GRMHD) sources requires simultaneous access to many fluid snapshots and is memory-intensive. We introduce CoportSL, the first contribution-constrained hybrid slow-light framework for time-dependent full-Stokes imaging. It uses emission, absorption, and Faraday contributions to identify where fluid evolution must be retained, applies fast light elsewhere, and loads only snapshots spanning the relevant delays. Tests with M87*-like magnetically arrested disk GRMHD data show that the contribution-based region and delay-based snapshot restrictions each keep normalized full-image Stokes differences below $4\times10^{-3}$ relative to the corresponding complete calculation. At this accuracy, CoportSL requires 75.3% and 44.7% fewer snapshot layers for near-horizon and jet images, respectively; its per-frame slow-light transfer time remains comparable to fast light. For the two configurations, source-code estimates place the capacities of the principal data structures at 255-657 GiB for a fixed public ipole version and 20.2-37.3GiB for CoportSL, bringing both configurations within workstation-scale memory. Fast--slow comparisons further show close agreement in near-horizon variability, whereas jet variability follows similar overall trends but differs in local peaks and amplitudes; in both cases, fast light misses substantial full-Stokes spatial structure. As the next-generation Event Horizon Telescope (ngEHT) advances toward dynamical imaging and spatially resolved polarimetry, CoportSL provides a computationally practical way to model full-Stokes finite-light-travel-time signatures in extended black hole systems.
Comments24 pages, 11 figures, 2 tables
