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（在第一颗恒星形成之前）被认为在大爆炸后大约5亿年结束，当时早期的光源产生了足够的高能光子来吸收中性氢。这个时期被称为再电离。这是第一个星系形成的时候。但是再电离到底是什么时候发生的，持续了多长时间？使中性气体电离的来源是什么？是第一个星系还是黑洞的吸积？这个项目将通过使用世界上最好的望远镜来回答这些问题。观测将包括第一批星系的图像和光谱，这将使我们能够第一次瞥见这一重要群体的化学组成。该项目还包括一个强有力的教育/公共外联部分。为了帮助培养未来的科学家，PI将为K-12学生开发一个观察课程。PI和co-PI也在为非科学专业的学生开发课程。再电离时代意味着宇宙从不透明到透明的转变，但人们对此知之甚少。什么时候开始/结束的？是不平整的还是光滑的？星系是如何重塑宇宙的（如果它们真的存在的话）？最早期的星系有什么性质？为了回答这些问题，在过去的几十年里，一些调查已经探索了高红移宇宙在逐渐增加的深度。然而，他们仍然缺乏样本量或深度（或两者兼而有之）。从这些调查中得出的结论是，这些问题的答案很可能与更暗的星系的性质有关。这个项目将通过对以前未被探索的红移为z6的暗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通过从深度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）提供再电离的时间轴，（2）确定第一个星系在这一过程中扮演的确切角色，（3）深入了解最早星系的恒星属性。该项目的教育/公众推广部分将包括为加州州立数学和科学暑期学校（COSMOS）制定一个针对K-12学生的观察课程。此外，研究人员还为非科学专业开发了名为“加利福尼亚物理学”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知识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