Cosmic Reionization and Its Feedback Effect on Galaxy Formation

宇宙再电离理论是星系形成理论中一个关键的缺失环节。再电离对宇宙微波背景的光谱、各向异性和极化，对高红移恒星和类星体形成的特征，以及对星系的质量谱和内部特征有许多可观察到的后果。该项目将使用宇宙辐射转移、气体和N体动力学模拟来解决冷暗物质模型中再电离理论及其对星系形成的反馈中的前沿问题，以便预测这些可观察到的特征。这包括(1)计算宇宙学这方面的测试、比较和标准；(2)具有足够动态范围的自调节再电离的第一次大规模辐射传递模拟；(3)小尺度结构对再电离的影响；(4)红移21厘米背景；(5)斑块再电离对CMB温度各向异性的影响；(6)第一族III星的气体动力学反馈对第二代恒星形成的影响。工作包括开创性地开发将辐射传递纳入模拟的计算方法和算法。这项研究将有助于研究生的培训和学习。该小组包括代表性不足的群体，并有相当数量的国际合作者。这项活动将加强全球和当地的研究基础设施。

AST-0708176ShapiroThe theory of cosmic reionization is a critical missing link in the theory of galaxy formation. Reionization has numerous observable consequences on the spectrum, anisotropy and polarization of the Cosmic Microwave Background, on signatures of high-redshift star and quasar formation, and on the mass spectrum and internal characteristics of galaxies. This project will use cosmological radiative transfer, gas and N-body dynamics simulations to address frontier problems in the theory of reionization and its feedback on galaxy formation in the Cold Dark Matter model, in order to predict these observable signatures. This includes (1) tests, comparisons, and standards for this aspect of computational cosmology; (2) the first large-scale radiative transfer simulations of self-regulated reionization with sufficient dynamic range; (3) the impact of small-scale structure on reionization; (4) the redshifted 21-cm background; (5) the effect of patchy reionization on CMB temperature anisotropy; and (6) the gas dynamical feedback of the first Population III stars on the second generation of star formation.The work involves the pioneering development of computational methodologies and algorithms for incorporating radiative transfer in simulations. The research will contribute to graduate training and learning. The team includes under-represented groups and has a significant number of international collaborators. This activity will enhance the global and the local research infrastructures.