First Light In The Universe: Probing the End Of The Dark Ages

宇宙中的第一道曙光：探索黑暗时代的终结

• 批准号: 0205738
• 负责人: Piero Madau
• 金额: $ 22.27万
• 依托单位: University of California-Santa Cruz
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-09-01 至 2006-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0205738&HistoricalAwards=false
• 关键词: First; Light; Universe; Probing; End

AST 0205738MadauIn currently popular cosmological scenarios at very early times, the gas within protogalactic halos with masses comparable to those of present-day dwarf ellipticals experienced rapid cooling and fragmentation. These fragments formed massive stars , which in turn synthesized heavy elements, and exploded as Type II supernovae, enriching the surrounding medium. These subgalactic stellar systems then generated the ultraviolet radiation and mechanical energy that reheated and reionized most of the hydrogen in the cosmos. The history of the Universe during and soon after these crucial formative stages is recorded in the thermal state, ionization degree, and chemical composition of the all-pervading intergalactic medium (IGM). Throughout the epoch of structure formation, the IGM becomes clumpy under the influence of gravity, and acts as a source for the gas that accretes, cools, and forms stars within subgalactic fragments, and as a sink for the metal enriched material, energy, and radiation which they eject. The study of the gaseous and stellar content of the high-redshift Universe thus provides invaluable insight into this era and the basic processes that govern the collapse, cooling, and evolution of some of the earliest formed cosmological structures. This theoretical project will study the epoch of .first light, the astrophysics of protogalactic systems, the intergalactic medium and quasar absorbers in the context of current theories of galaxy formation. It will focus on a series of critical questions in each of these interrelated areas: (1) cosmological reionization, (2) the epoch of first light, and (3) protogalaxy halos, SN-driven winds, and the metal enrichment of the IGM. A coordinated approach will be pursued involving theoretical studies of the controlling physical processes, and direct numerical simulation of their effects within the current paradigm for structure formation. The results of this program should aid in the planning for future large observational facilities such as the California Extremely Large Telescope, the Low Frequency Array, the Square Kilometer Array, and the Next Generation Space Telescope.***

AST 0205738MADAUIN目前在很早的时候流行的宇宙学场景，与当今矮人椭圆形相当的质量的质量光环中的气体经历了快速的冷却和碎片化。这些碎片形成了巨大的恒星，进而构成了重型元素，并爆炸为II型超新星，丰富了周围的介质。 然后，这些亚星体恒星系统产生了紫外线和机械能，从而将大部分氢在宇宙中重新加热和回归。 在这些关键形成阶段期间和之后不久，宇宙的历史记录在热状态的热状态，电离程度和化学成分的全层面间层间培养基（IGM）。在整个结构形成时期，IgM在重力的影响下变得块状，并充当气体片段内的气体，冷却和形成恒星的来源，以及作为金属富集材料，能量，能量和金属的水槽它们弹出的辐射。因此，对高红移宇宙的气态和恒星含量的研究提供了对这个时代的宝贵见解，以及控制了一些最早形成的宇宙学结构的崩溃，冷却和演变的基本过程。这个理论项目将在当前的星系形成理论的背景下，研究。首先光，原生结肠系统的天体物理学，播层间培养基和类星体吸收器。它将重点关注这些相互关联的区域中的一系列关键问题：（1）宇宙学的回离，（2）第一光的时代，以及（3）Protogalaxy Halos，SN驱动风和IgM的金属富集。将采用一种协调的方法，涉及控制物理过程的理论研究，并在当前的结构形成范式中直接对其效应进行数值模拟。该计划的结果应有助于计划未来的大型观察设施，例如加利福尼亚极大的望远镜，低频阵列，平方公里阵列和下一代太空望远镜。***