A New Generation of Absorption Spectroscopy Experiments Probing the Epoch of Reionization

新一代吸收光谱实验探索再电离时代

• 批准号: 2307180
• 负责人: Joseph Hennawi
• 金额: $ 54.39万
• 依托单位: University of California-Santa Barbara
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-07-15 至 2026-06-30
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2307180&HistoricalAwards=false
• 关键词: New; Generation; Absorption; Spectroscopy; Experiments

In the early universe, much of the gas between galaxies was neutral hydrogen. The early generations of stars, galaxies, and black holes emitted radiation that ionized this gas. The period of time when this occurred is known as the epoch of reionization. The history of reionization sheds light on the nature and evolution of the early universe. This project will use observations of the most distant quasars to study the ionization state of the hydrogen gas between us and the quasars. The project will also study the enrichment of the gas by heavier elements produced in the first stars. The project will also support one graduate student, partially support a post-doc, and provide summer stipends for two undergraduates from Hispanic Serving Institutions in years 1 and 2. The project will also provide indirect support for the maintenance and distribution of the PypeIt software package for spectroscopic data reduction.The project will use spectroscopic data from the Keck telescope for 200 quasar sightlines to study the intergalactic medium (IGM). The quasars are all at redshifts greater than 6. The spectroscopic analysis will allow for the identification of the local ionization status of the IGM as well as identifying evidence of enrichment of the IGM with metals from the first supernovae. By identifying the local ionization status around the quasars, the project will also provide a history of the radiative history of the quasar -- thus allowing for a better understanding of how these supermassive black holes grew to such large masses within 800 Myr after the Big Bang. The project will conduct end-to-end analyses encompassing observations, theoretical modeling, state-of-the-art simulations, and Bayesian inference to provide a solid methodological footing for study of the epoch of reionization.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

在早期宇宙中，星系之间的大部分气体是中性氢。早期的恒星、星系和黑洞发出的辐射使这种气体电离。发生这种情况的时期称为再电​​离时期。再电离的历史揭示了早期宇宙的本质和演化。该项目将利用对最遥远类星体的观测来研究我们与类星体之间氢气的电离状态。该项目还将研究第一代恒星产生的较重元素对气体的富集情况。该项目还将支持一名研究生，部分支持一名博士后，并为西班牙服务机构的两名本科生提供第一年和第二年的暑期津贴。该项目还将为光谱数据缩减的 PypeIt 软件包的维护和分发提供间接支持。该项目将使用凯克望远镜 200 个类星体视线的光谱数据来研究星际介质 （IGM）。这些类星体的红移均大于 6。光谱分析将能够识别 IGM 的局部电离状态，并识别 IGM 中来自第一颗超新星的金属富集的证据。通过识别类星体周围的局部电离状态，该项目还将提供类星体辐射历史的历史，从而更好地了解这些超大质量黑洞如何在大爆炸后 800 迈尔内增长到如此大的质量。该项目将进行涵盖观察、理论建模、最先进的模拟和贝叶斯推理的端到端分析，为再电离时代的研究提供坚实的方法论基础。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。