标题： 一种星系-星系引力透镜和团星系重建的同时最大似然方法 显示英文标题

标题： A simultaneous maximum likelihood approach for galaxy-galaxy lensing and cluster lens reconstruction

摘要： 在之前的一篇论文中，我们研究了通过弱引力透镜来约束星系团星系质量分布的方法。 我们得出结论，一种全面的方法应同时处理单个星系团星系的引力透镜效应以及来自一般星系团成分的引力透镜效应。 为此，我们现在开发了一种非参数最大似然星系团重建算法，该算法可以隐式地考虑星系团星系的存在。 该方法包括一种类似熵的正则化方案，并直接使用单个源星系图像的椭率作为观测值，而不是依赖于平均椭率场。 星系团星系的质量分布由参数化模型描述。 对于每组星系参数，星系团重建算法可以确定与星系团星系的存在以及背景星系图像椭率观测值一致的全局潜在星系团成分的最佳表示。 模拟测试得到了令人信服且稳健的结果。 我们将该方法应用于Cl0939+4713星系团的WFPC2图像，并检测到了明亮椭圆星系的引力透镜效应。 我们认为这一应用是对我们技术的成功测试。 然而，我们分析的图像尺寸较小，尚不足以得出关于星系团星系质量分布的有力结论。 显示英文摘要

摘要： In a previous paper we investigated means for constraining the mass distribution of cluster galaxies by weak lensing. We concluded that a comprehensive method should treat the lensing effects of individual cluster galaxies and those resulting from a general cluster component simultaneously. To this end we now develop a non-parametric maximum likelihood cluster reconstruction algorithm that can implicitly take into account the presence of cluster galaxies. The method includes an entropy-like regularization prescription and directly uses the ellipticities of individual source galaxy images as observables rather than relying on an averaged ellipticity field. The mass distribution of cluster galaxies is described by parametrized models. For each set of galaxy parameters the cluster reconstruction algorithm allows to determine the best representation of the global underlying cluster component that is consistent with the presence of the cluster galaxies and the observed image ellipticities of background galaxies. Tests with simulations yielded convincing and robust results. We applied the method to a WFPC2 image of the cluster Cl0939+4713 and obtained a detection of the lensing effects of luminous elliptical cluster galaxies. We consider this application as a successful test of our technique. However, the small size of the image we analysed does not yet allow to draw strong conclusions regarding the mass distribution of cluster galaxies.