Collaborative Research: The Final Frontier: Spectroscopic Probes of Galaxies at the Epoch of Reionization

合作研究：最后的前沿：再电离时期的星系光谱探测器

• 批准号: 1810822
• 负责人: Tommaso Treu
• 金额: $ 12.2万
• 依托单位: University of California-Los Angeles
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-08-15 至 2021-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1810822&HistoricalAwards=false
• 关键词: Collaborative; Research; Final; Frontier; Spectroscopic

The cosmic Dark Ages (before the first stars formed) are thought to have ended around 500 million years after the Big Bang when early light sources produced enough energetic photons to ionize the neutral hydrogen. This era is referred to as reionization. It is when the first galaxies formed. But when exactly did reionization occur and how long did it last? What were the sources responsible for ionizing the neutral gas? Was it the first galaxies or accretion onto black holes? This project will answer these questions by using the best telescopes in the world. The observations will include images and spectra of the first galaxies, which enable a first glimpse of the chemical composition of this important population. The project also includes a strong educational/public outreach component. To help train tomorrow's scientists, the PI will develop an observing course intended for K-12 students. The PI and co-PI are also developing courses for non-science majors.The epoch of reionization, which signified the transformation of the universe from opaque to transparent, is poorly understood. When did it start/end? Was it patchy or smooth? How did galaxies reionize the universe (if they did)? What are the properties of the earliest galaxies? To answer these questions, over the last decades, several surveys have explored the high redshift universe at progressively increasing depth. However, they still either lack the sample size or depth (or both). What emerges from these surveys is that the answers to these questions are likely tied to the properties of even fainter galaxies. This project will address the problem by conducting a spectroscopic study of a large sample of previously unexplored faint galaxy populations at redshifts z 6. This will be achieved by using galaxy clusters that serve as cosmic telescopes and by pre-selecting sources from deep ancillary imaging and low-resolution spectroscopy data. This project will (1) provide the timeline of reionization, (2) identify the exact role first galaxies played in this process, and (3) give insight on the stellar properties of the earliest galaxies. The educational/public outreach component of this project will include developing an observing course for California State Summer School for Mathematics and Science (COSMOS), intended for K-12 students. In addition, the investigators are also developing new university courses entitled the "Physics of California'' and "The physics of sustainable energy'' for non- science majors.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.

宇宙黑暗时代（第一批恒星形成之前）被认为在大爆炸后约 5 亿年结束，当时早期光源产生了足够的高能光子来电离中性氢。这个时代被称为再电离。这是第一个星系形成的时候。但再电离到底是什么时候发生的以及持续了多长时间？电离中性气体的来源是什么？它是第一个星系还是黑洞的吸积物？该项目将利用世界上最好的望远镜来回答这些问题。观测结果将包括第一批星系的图像和光谱，使人们能够第一眼看到这个重要星系的化学成分。该项目还包括强大的教育/公共宣传部分。为了帮助培训未来的科学家，PI 将为 K-12 学生开发一门观察课程。 PI和co-PI也在为非科学专业的学生开发课程。再电离时代标志着宇宙从不透明到透明的转变，但人们对它知之甚少。什么时候开始/结束？是斑驳的还是光滑的？星系是如何使宇宙重新电离的（如果有的话）？最早的星系有哪些特性？为了回答这些问题，在过去的几十年里，一些调查在逐渐增加的深度上探索了高红移宇宙。然而，它们仍然缺乏样本量或深度（或两者）。从这些调查中得出的结论是，这些问题的答案可能与甚至更暗的星系的特性有关。该项目将通过对先前未探索的红移 z 6 微弱星系群的大样本进行光谱研究来解决这个问题。这将通过使用充当宇宙望远镜的星系团以及从深层辅助成像和低分辨率光谱数据中预先选择源来实现。该项目将（1）提供再电离的时间表，（2）确定第一个星系在此过程中所扮演的确切角色，以及（3）深入了解最早星系的恒星特性。该项目的教育/公共推广部分将包括为加州数学和科学暑期学校 (COSMOS) 开发一门观察课程，供 K-12 学生使用。此外，研究人员还正在为非科学专业的学生开发题为“加州物理学”和“可持续能源物理学”的新大学课程。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。

项目成果

Constraining Lyman-alpha spatial offsets at 3 < z < 5.5 from VANDELS slit spectroscopy

根据 VANDELS 狭缝光谱将 Lyman-alpha 空间偏移限制在 3 < z < 5.5

• DOI: 10.1093/mnras/stz1768
• 发表时间: 2019
• 期刊: Monthly Notices of the Royal Astronomical Society
• 影响因子: 4.8
• 作者: Hoag, A;Treu, T;Pentericci, L;Amorin, R;Bolzonella, M;Bradač, M;Castellano, M;Cullen, F;Fynbo, J P;Garilli, B
• 通讯作者: Garilli, B

The impact of scatter in the galaxy UV luminosity to halo mass relation on Ly α visibility during the epoch of reionization

再电离时期星系紫外光度与晕质量关系的散射对 Lyα 能见度的影响

• DOI: 10.1093/mnras/staa1178
• 发表时间: 2020
• 期刊: Monthly Notices of the Royal Astronomical Society
• 影响因子: 4.8
• 作者: Whitler, Lily R;Mason, Charlotte A;Ren, Keven;Dijkstra, Mark;Mesinger, Andrei;Pentericci, Laura;Trenti, Michele;Treu, Tommaso
• 通讯作者: Treu, Tommaso

Candidate Population III stellar complex at z = 6.629 in the MUSE Deep Lensed Field

MUSE 深透镜视场中 z = 6.629 处的候选族 III 恒星复合体

• DOI: 10.1093/mnrasl/slaa041
• 发表时间: 2020
• 期刊: Monthly Notices of the Royal Astronomical Society: Letters
• 作者: Vanzella, E;Meneghetti, M;Caminha, G B;Castellano, M;Calura, F;Rosati, P;Grillo, C;Dijkstra, M;Gronke, M;Sani, E
• 通讯作者: Sani, E

The Mass–Metallicity Relation at z ≃ 8: Direct-method Metallicity Constraints and Near-future Prospects

• DOI: 10.3847/1538-4357/abb943
• 发表时间: 2020-06
• 期刊: The Astrophysical Journal
• 作者: T. Jones;R. Sanders;G. Roberts-Borsani;R. Ellis;N. Laporte;T. Treu;Y. Harikane

Inferences on the timeline of reionization at z ∼ 8 from the KMOS Lens-Amplified Spectroscopic Survey

• DOI: 10.1093/mnras/stz632
• 发表时间: 2019-01
• 期刊: Monthly Notices of the Royal Astronomical Society
• 影响因子: 4.8
• 作者: C. Mason;A. Fontana;T. Treu;K. Schmidt;A. Hoag;L. Abramson;R. Amorín;M. Bradač;L. Guaita