New Approach to Gravitational Clustering and Improved Cosmological Parameter Estimation

这个项目专注于两个领域：一种新的引力星团分析方法，可以探测非线性系统；以及改进从星系调查中确定宇宙学参数的方法。第一部分将使用重整化微扰理论，首先了解重子声振荡的非线性演化及其对星系探测的影响，然后描述小尺度暗物质功率谱，并由此区分广义相对论的修正和作为宇宙加速的原因的暗能量的存在。第二部分涉及通过使用星系双谱和其他高阶统计量来改进宇宙学参数估计，以及通过提高公开可用的晕建模程序PTHalos的准确性、效率和实用性。研究合作包括一名博士后研究员和研究生，研究结果的某些方面将被整合到研究生和本科生的教学中。PTHalos的公开发布将对天文学社区具有广泛的实用价值。

AST-0607747ScoccimarroThis project focuses on two areas: a new analytic approach to gravitational clustering that can probe the nonlinear regime, and improving the determination of cosmological parameters from galaxy surveys. Part one will use renormalized perturbation theory, firstly, to understand the nonlinear evolution of baryon acoustic oscillations and their impact on galaxy surveys, and secondly, to describe the dark matter power spectrum at small scales, and thence to differentiate between modifications of general relativity and the presence of a dark energy, as the cause of cosmic acceleration. The second part involves improvements in cosmological parameter estimation by using the galaxy bispectrum and other higher-order statistics, and by improving the accuracy, efficiency and usefulness of the publicly available halo modeling program called PTHalos.The research collaboration includes a postdoctoral fellow and graduate students, and aspects of the results will be integrated into graduate and undergraduate instruction. The public release of PTHalos will be of wide utility to the astronomical community.