Collaborative Research: A Three-Dimensional Analysis of the Gas and Dark Matter in the CLASH Clusters of Galaxies

该团队将使用他们最先进的模型来分析25个星系团的亚毫米、光学和X射线观测。该模型将揭示星团的形状是棒球、雪茄、煎饼还是更复杂的东西。一旦星系团的形状已知，星团质量将以前所未有的精度被估计出来。这将为宇宙学家提供一个强大的新工具来研究宇宙为什么会这样演化。该团队将向公众发布他们的建模代码。高级团队成员将培训初级成员。该团队还将开发免费的在线教材，并与低收入地区的高中生互动。该团队将分析对星系团的广泛观测，以形成其暗物质和气体物质的三维重建。三个维度的推论源于X射线和Sunyaev-Zeldovich信号在星系团内如何变化的差异。重建将极大地提高星系团质量估计的准确性。这反过来将改善基于星系团的宇宙学。该团队的具体目标是测量每个星团的(1)长轴取向为/-15度，轴比为/-0.15；(2)非热压与热压的比率，在郊区达到/-0.2；以及(3)三维质量分布，在浓度参数中达到/-0.1。为了量化测量的稳健性，该团队还将评估模拟星系团的模拟观测的(1)、(2)和(3)。

The team will use their state-of-the-art model to analyze submillimeter, optical and X-ray observations of 25 clusters of galaxies. The model will reveal if the clusters are shaped like baseballs, cigars, pancakes or something more complex. Once the cluster shapes are known, the cluster masses will be estimated with unprecedented accuracy. This will give cosmologists a powerful new tool to study why the universe evolves as it does. The team will release their modeling code to the public. Senior team members will train junior members. The team will also develop free on-line teaching materials and interact with high school students in low-income areas.The team will analyze extensive observations of clusters of galaxies to form three-dimensional reconstructions of their dark matter and gaseous matter. Inferences in three dimensions stem from differences in how the X-ray and Sunyaev-Zeldovich signals vary within a cluster. The reconstructions will vastly improve the accuracy of cluster-mass estimates. This, in turn, will improve cluster-based cosmology. The team's specific goals are to measure for each cluster (1) the major-axis orientation to +/-15 degrees and the axial ratio to +/-0.15; (2) the ratio of non-thermal to thermal pressures, achieving +/-0.2 in the outskirts; and (3) the three-dimensional mass profile, achieving +/-0.1 in the concentration parameter. To quantify the robustness of the measurements, the team will also evaluate (1), (2) and (3) for mock observations of simulated clusters.