The Extreme Galaxy Reference Sample: Low Metallicity Galaxies Across Cosmic Time

极端星系参考样本：宇宙时间内的低金属丰度星系

• 批准号: 1909198
• 负责人: Dawn Erb
• 金额: $ 38.14万
• 依托单位: University of Wisconsin-Milwaukee
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-09-01 至 2024-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1909198&HistoricalAwards=false
• 关键词: Extreme; Galaxy; Reference; Sample; Low

Faint, low-mass galaxies are a population of cosmological importance: numerous at high redshifts, they are the most likely source of the photons that re-ionized the universe. Characterization of such galaxies remains one of the key problems in astrophysics. This project will create a publicly-available reference sample of the most highly ionized galaxies, the Extreme Galaxy Reference Sample (EGRS). The EGRS will be used to quantify the diversity in the properties of low-metallicity galaxies and their surrounding gas, in the local universe and at the peak epoch of star formation. The most extensive knowledge of the physical conditions in the galaxies that likely re-ionized the universe comes not from studying reionization-era sources directly, but from detailed examination of plausibly similar objects at low and moderate redshifts. The project includes a multi-layered strategy of sharing science with many audiences, from the general public to undergraduate students, and including curriculum development, outreach, and mentoring of students from under-represented populations.Outstanding questions include the factors that enable the escape of ionizing radiation, the intrinsic ionizing spectra of the most extreme and highly ionized galaxies, and the role of feedback in shaping the properties of the circumgalactic medium (CGM) and enabling ionizing photon escape. The EGRS has two pieces: 1) the Extreme Census of the Local Universe (ExCLU), an imaging survey using four wavelength-adjacent narrowband filters to cover an extraordinarily wide area of 26,470 square degrees that will find tens of thousands of the rarest and most extreme galaxies in the local universe, and enabling studies of their halo masses, evolutionary states, stellar populations, intrinsic ionizing spectra and feedback-related properties, and 2) comprehensive studies of a smaller, carefully selected sample of galaxies at redshift about two, to map the CGM with Lyman-alpha emission and quantify feedback with deep rest-frame ultraviolet imaging, supplemented by higher signal-to-noise, higher resolution studies of gravitationally lensed galaxies. EGRS will provide the community with a baseline for the study of low-mass, low-metallicity galaxies across cosmic time.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.

微弱的、低质量的星系是一个具有宇宙学重要性的群体：它们有大量的高红移，它们是使宇宙再电离的光子的最有可能的来源。这类星系的特征仍然是天体物理学中的关键问题之一。该项目将创建一个公开可用的最高电离星系的参考样本，即极端星系参考样本（EGRS）。EGRS将用于量化低金属丰度星系及其周围气体的特性多样性，在当地宇宙和恒星形成的高峰时期。关于可能使宇宙再电离的星系的物理条件的最广泛的知识不是来自对再电离时代来源的直接研究，而是来自对低红移和中等红移似乎相似的物体的详细检查。该项目包括一个多层次的战略，与从普通公众到本科生的众多受众分享科学，并包括课程开发、推广和对代表性不足群体学生的指导。悬而未决的问题包括使电离辐射逃逸的因素，最极端和高度电离星系的固有电离光谱，以及反馈在形成环星系介质（CGM）特性和使电离光子逃逸中的作用。EGRS有两个部分：1)局部宇宙的极端普查（exu），这是一项成像调查，使用四个波长相邻的窄带滤波器覆盖26,470平方度的非常宽的区域，将发现局部宇宙中数万个最稀有和最极端的星系，并能够研究它们的光晕质量，演化状态，恒星种群，固有电离光谱和反馈相关特性；精心挑选红移约为2的星系样本，用莱曼- α发射来绘制CGM，用深静止帧紫外成像来量化反馈，辅以更高的信噪比、更高分辨率的引力透镜星系研究。EGRS将为研究跨宇宙时间的低质量、低金属丰度星系提供基线。该奖项反映了美国国家科学基金会的法定使命，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

SDSS J1059+4251, a Highly Magnified z ∼ 2.8 Star-forming Galaxy: ESI Observations of the Rest-frame UV Spectrum

SDSS J1059 4251，高度放大的 z ≤ 2.8 恒星形成星系：ESI 对静止框架紫外光谱的观测

• DOI: 10.3847/1538-4357/ac24a2
• 发表时间: 2021
• 期刊: The Astrophysical Journal
• 作者: Citro, Annalisa;Erb, Dawn K.;Pettini, Max;Auger, Matthew W.;Becker, George D.;James, Bethan L.
• 通讯作者: James, Bethan L.

The Circumgalactic Medium of Extreme Emission Line Galaxies at z∼2: Resolved Spectroscopy and Radiative Transfer Modeling of Spatially Extended Lyα Emission in the KBSS-KCWI Survey*

z−2 处极端发射线星系的环星系介质：KBSS-KCWI 巡天中空间扩展 Lyα 发射的分辨光谱学和辐射传递模型*

• DOI: 10.3847/1538-4357/acd849
• 发表时间: 2023
• 期刊: The Astrophysical Journal
• 作者: Erb, Dawn K.;Li 李智, Zhihui 慧.;Steidel, Charles C.;Chen 陈昱, Yuguang 光.;Gronke, Max;Strom, Allison L.;Trainor, Ryan F.;Rudie, Gwen C.
• 通讯作者: Rudie, Gwen C.

Characterizing Extreme Emission Line Galaxies. II. A Self-consistent Model of Their Ionizing Spectrum*

描述极端发射线星系的特征。

• DOI: 10.3847/1538-4357/ac8f2c
• 发表时间: 2022
• 期刊: The Astrophysical Journal
• 作者: Olivier, Grace M.;Berg, Danielle A.;Chisholm, John;Erb, Dawn K.;Pogge, Richard W.;Skillman, Evan D.
• 通讯作者: Skillman, Evan D.