Cosmological evolution and very high energy astrophysics

宇宙演化和极高能天体物理学

• 批准号: 0855345
• 负责人: Todor Stanev
• 金额: $ 4万
• 依托单位: University of Delaware
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-07-01 至 2012-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0855345&HistoricalAwards=false
• 关键词: Cosmological; evolution; very; energy; astrophysics

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). The work on this project will be dedicated to studies of the cosmological evolution of the cosmic ray sources and of the extragalactic light background. It is currently far from obvious which is the best proxy for the cosmological evolution of the UHECR sources since we are not certain what the sources are. The PI will thus attempt to combine the information from different ultra high and very high energy experiments, including (hopefully) the future detection of very high energy neutrinos, and reach conclusions related to cosmological evolution. The PI proposes theoretical work and data analysis that will lead to a better understanding of the cosmological evolution of different types of powerful extragalactic sources and to identification of the sources of ultrahigh energy cosmic rays (UHECR) - the highest energy nuclei in the Universe. Special attention will be paid to the cosmological evolution of different types of possible sources. The resolution of this evolution dominates the production of secondary fluxes of cosmogenic gamma rays and neutrinos from ultra high energy cosmic rays interactions in the universal photon fields. These include the microwave background and the extragalactic background light (EBL) in infrared, optical and UV ranges. EBL plays important role in the production of the cosmogenic fluxes and in the absorption of TeV gamma rays - both cosmogenic ones as well as of those coming from different extragalactic sources. The comparison of the absorption of the gamma rays coming from different sources may reveal the cosmological evolution of EBL that is now being disputed.The results of the proposed work will yield information about a much wider range of global astrophysical and cosmological parameters which underscores the broader impact of this work. The PI is Co-Director of the Erice International School for Cosmic Rays Astrophysics (ISCRA) and gives lectures there to young scientists. The School meets every two years and has on the average 60 students (graduate students and postdocs) and 12 lecturers.

该奖项是根据2009年美国复苏和再投资法案（公法111-5）资助的。该项目的工作将致力于研究宇宙射线源的宇宙学演变和河外光背景。目前还远不清楚哪一个是UHECR源的宇宙学演化的最佳代理，因为我们不确定源是什么。因此，PI将尝试联合收割机结合来自不同的超高能和甚高能实验的信息，包括（希望）未来对甚高能中微子的探测，并得出与宇宙学演化有关的结论。PI提出了理论工作和数据分析，这将导致更好地理解不同类型的强大河外源的宇宙学演化，并确定宇宙中能量最高的核-高能宇宙射线（UHECR）的来源。 将特别注意不同类型的可能来源的宇宙学演化。 这种演变的分辨率占主导地位的宇宙成因的伽马射线和中微子的超高能宇宙射线在宇宙光子场的相互作用的二次通量的生产。这些包括微波背景和河外背景光（EBL）在红外线，光学和紫外线范围。EBL在宇宙起源通量的产生和TeV伽马射线的吸收中起着重要的作用-这两种宇宙起源的伽马射线以及来自不同河外源的伽马射线。来自不同来源的伽马射线的吸收的比较可能会揭示EBL的宇宙学演化，现在正在争议的结果，拟议的工作将产生有关更广泛的全球天体物理和宇宙学参数的信息，这强调了这项工作的更广泛的影响。PI是Erice国际宇宙射线天体物理学院（ISCRA）的联合主任，并在那里为年轻科学家讲课。学校每两年举行一次会议，平均有60名学生（研究生和博士后）和12名讲师。