Theoretical Models of Helium Reionization

氢和氦的再电离是宇宙历史上具有里程碑意义的事件，构成了星系间介质(IGM)的重要相变，并影响着后来各地的结构形成。尽管氢再电离受到了最多的关注，但关于氦的令人兴奋的新数据来自于中等红移类星体的远紫外光谱。这个项目旨在建立一个物理激励的、全面的氦再电离模型，包括源聚集、不均匀性以及源和吸收体之间的关联。分析模型将与数值模拟进行比较，然后根据现有和未来的观测数据进行测试。最终结果将揭示许多关于来源的内在属性及其与IGM的关系。教育部分紧密结合，包括研究生的论文工作，以及耶鲁大学现有课程的本科生研究；该项目是模块化的，非常适合短期但有意义的研究。这项工作应该会在天体物理界引起广泛的反响，并对类星体的演化、IGM和结构形成产生影响。

AST-0607470FurlanettoThe reionization of hydrogen and helium are landmark events in the history of the Universe, constituting important phase transitions for the intergalactic medium (IGM) and impacting later structure formation everywhere. Although hydrogen reionization has received the most attention, exciting new data on helium are coming from far-ultraviolet spectra of moderate redshift quasars. This project aims to build a physically motivated, comprehensive model for helium reionization, including source clustering, inhomogeneities, and the correlations between sources and absorbers. The analytic model will be compared to numerical simulations and then tested against existing and future observations. The end result will reveal a lot about the intrinsic properties of the sources and their relation to the IGM.There is a tightly integrated educational component, including a graduate student's thesis work, and undergraduate research through existing programs at Yale University; the project is modular and lends itself well to short-term but meaningful research. This work should have wide repercussions within the astrophysical community, with implications for quasar evolution, the IGM, and structure formation.