论文标题
脱粒机:没有浪费的幸运成像
The Thresher: Lucky Imaging without the Waste
论文作者
论文摘要
在传统的幸运成像(TLI)中,使用高框架速率相机拍摄了许多同一场景的连续图像,除最清晰的图像外,所有图像都在构造最终的移动和添加图像之前被丢弃。在这里,我们基于在线多框架盲解卷积,提出了此类数据的替代图像分析管道 - 脱粒机。它利用所有可用的数据在合理的计算限制的背景下获得天文场景的最佳估计;它不需要对图像中的点传播函数的事先估算,也不需要场景中可以提供此类估计值的点源的知识。最重要的是,它旨在返回的场景是基于可能性函数的最佳标量目标的最佳选择。因为它使用堆栈中的完整图像,所以Thresher在信号到噪声中的表现都优于TLI。当它解释个人框架PSF时,它在不会丢失角度分辨率的情况下进行此操作。我们证明了算法对在丹麦154万望远镜(由La Silla托管)获得的模拟数据和真实电子的CCD图像的有效性。我们还探讨了算法的当前局限性,并发现在此处介绍的图像模型的选择中,将磁通中的非线性引入到返回的场景中。可以在https://github.com/jah1994/thersher上查看该软件的持续开发。
In traditional lucky imaging (TLI), many consecutive images of the same scene are taken with a high frame-rate camera, and all but the sharpest images are discarded before constructing the final shift-and-add image. Here we present an alternative image analysis pipeline -- The Thresher -- for these kinds of data, based on online multi-frame blind deconvolution. It makes use of all available data to obtain a best estimate of the astronomical scene in the context of reasonable computational limits; it does not require prior estimates of the point-spread functions in the images, or knowledge of point sources in the scene that could provide such estimates. Most importantly, the scene it aims to return is the optimum of a justified scalar objective based on the likelihood function. Because it uses the full set of images in the stack, The Thresher outperforms TLI in signal-to-noise; as it accounts for the individual-frame PSFs, it does this without loss of angular resolution. We demonstrate the effectiveness of our algorithm on both simulated data and real Electron-Multiplying CCD images obtained at the Danish 1.54m telescope (hosted by ESO, La Silla). We also explore the current limitations of the algorithm, and find that for the choice of image model presented here, non-linearities in flux are introduced into the returned scene. Ongoing development of the software can be viewed at https://github.com/jah1994/TheThresher.