论文标题
$ \ it cod：$通过拓扑优化的过天体重建形状重建的算法
$\it COD:$ An Algorithm for Shape Reconstruction of Transiting Celestial Bodies through Topological Optimization
论文作者
论文摘要
我们介绍了一种新颖的算法，$ \ textit {cod} $ - 紧凑型不透明度分布，用于对天体的形状重建，该天体已被观察到，使用神秘学的光度法时间序列观察，该天体被观察到了恒星。 $ \ textit {cod} $找到了对光曲线反转问题的解决方案，对于具有大约凸形形状的光学较厚的occulter，以及相对于隐匿性星的估计，其大小，冲击参数和速度的估计值。该算法基于一种优化方案，该方案使用拓扑约束和Occulter几何形状的目标函数。问题的约束遵循线性关系，这使线性编程优化用作数学框架。进行了多个算法测试，所有这些测试都导致模拟对象的模拟和获得的形状之间的高度相关性，其预计速度和水平尺寸的$ 5 \％$在其影响参数的$ 5 \％$中，其预计速度和水平尺寸为0.1美元。这些测试包括Phobos的日食的视频，如NASA的好奇心漫游者所看到的那样，该视频被倒入相应的光曲线中并随后重建。我们将$ \ textit {cod} $应用于VVV-Wit-08的神秘案例 - 一个巨大的恒星的单个深层掩埋（$ \ sim 96 \％$），持续了200天以上。该分析没有假定Occulter的任何特定形状，它表明一个对象具有类似于$ \ sim 0.5 $的椭圆形的椭圆形分布，相对于运动方向，以$ \ sim 30 $度的倾斜度，具有类似于恒星半径。
We introduce a novel algorithm, $\textit{COD}$ -- Compact Opacity Distribution, for shape reconstruction of a celestial body that has been observed to occult a star, using the photometric time-series observations of the occultation. $\textit{COD}$ finds a solution to the light-curve inversion problem for an optically thick occulter having an approximately convex shape, together with an estimate of its size, impact parameter and velocity, relative to the occulted star. The algorithm is based on an optimization scheme that uses topological constraints and an objective function for the geometry of the occulter. The constraints of the problem follow linear relations, which enable the use of linear programming optimization as the mathematical framework. Multiple tests of the algorithm were performed, all of which resulted in high correlations between the simulated and obtained shapes of the occulting objects, with errors within $5\%$ in their projected velocities and horizontal sizes, and within $0.1$ in their impact parameters. These tests include a video of a solar eclipse by Phobos, as seen by NASA's Curiosity rover, which was collapsed into its corresponding light curve and reconstructed afterwards. We applied $\textit{COD}$ to the mysterious case of VVV-WIT-08 -- a single deep occultation ($\sim 96 \%$) of a giant star lasting for over 200 days. The analysis, which did not assume any specific shape of the occulter, suggested an object with a projected opacity distribution resembling an ellipse with an eccentricity of $\sim 0.5$, tilted at $\sim 30$ degrees relative to the direction of motion, with a semi-minor axis similar to the stellar radius.
