From Theory to the Sky: Observable Features of Clusters of Galaxies

AST-0708150EvrardPower正在使用泛色探测方法对最大的束缚宇宙结构--星系团进行强有力的搜索。这些调查可以识别宇宙中所有最大质量的星系团，然后将挖掘这些星系团来寻找暗能量的线索。然而，准确的结论需要了解限制系统不确定性的天体物理学。这是一个计算项目，旨在提高对集群作为多组件、动态活动系统的理解。用一系列天体物理方法进行的最先进的模拟将描述星系团内在的、可见的内容如何与总质量和历元有关。同时研究多个特征将提供重要的、独立的测量之间的协方差的第一次估计，例如X射线温度和光度、光学丰度和气体总热能。模拟天空图将用于测试和改进星团检测方法。这些研究将对所有集群调查通用，将包括测量属性协方差的统计形式，了解预测来源混乱的原因和程度，以及测试合并驱动的瞬变的影响。该项目将培训学生进行涉及数据密集型高性能计算的分析。首席研究人员继续积极组织讲习班和会议，特别是那些强调该领域年轻研究人员的讲习班和会议，并打算在2009年春季举办讲习班，将观察员、计算模型师和理论家聚集在一起，形成关于星系团是天体物理人口的共识观点，为暗能量研究铺平道路。

AST-0708150EvrardPowerful searches for galaxy clusters, the largest bound cosmic structures, are underway using pan-chromatic detection methods. These surveys can identify all of the most massive clusters in the Universe, which will then be mined for clues to dark energy. However, accurate conclusions require understanding the astrophysics that limits systematic uncertainties. This is a computational project to improve understanding of clusters as multi-component, dynamically active systems. State-of-the-art simulations with a range of astrophysical treatments will characterize how the intrinsic, visible content of clusters relates to total mass and epoch. Studying multiple characteristics simultaneously will provide the first estimates of covariance between important, independent measures, such as X-ray temperature and luminosity, optical richness, and total gas thermal energy. Mock sky maps will be used to test and improve cluster detection methods. The studies will be of general use for all cluster surveys, and will include measuring the statistical form of property covariance, understanding the causes and magnitudes of projected source confusion, and testing the effects of merger-driven transients.This project will train students in analysis involving data-intensive, high performance computing. The lead researcher continues to be active in organizing workshops and conferences, especially those that emphasize young researchers in the field, and intends a spring 2009 workshop to bring together observers, computational modelers and theorists to develop a consensus view of clusters as an astrophysical population, paving the way for dark energy studies.