Dust Obscuration towards the Epoch of Reionization

迈向再电离时代的尘埃遮蔽

• 批准号: 1814034
• 负责人: Caitlin Casey
• 金额: $ 33.25万
• 依托单位: University of Texas at Austin
• 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: 2018-09-01 至 2022-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1814034&HistoricalAwards=false
• 关键词: Dust; Obscuration; towards; Epoch; Reionization

Deep-space images from the Hubble Space Telescope reveal the most distant galaxies in the Universe. These objects are groups of thousands to millions of stars like our sun. They are so distant that light from their stars has taken billions of years to reach us. Most galaxies this distant are visible in the deepest images from Hubble, but not all. Some galaxies contain a lot of dust, making them more difficult to see because the dust obscures starlight. Starlight heats the dust, which then re-radiates that energy at millimeter wavelengths. These dusty galaxies form stars very rapidly, and are important to our understanding of how stars form. Little is known about how common dusty galaxies were in the first few billion years after the Big Bang. This project will use all available data at millimeter wavelengths to estimate how common they were during those early times. This is important to our fundamental understanding of how the first galaxies formed. This project will also host students from under-represented minority backgrounds in astronomy research through the Texas Astronomy Undergraduate Research for Under- represented Students (TAURUS) program at UT Austin. The goal of the research program is to retain these excellent students in STEM careers.Taking census of the cosmic history of star-formation is a key goal of galaxy evolution surveys. However, measurements to date, particularly at the highest redshifts, are almost exclusively determined from unobscured star-formation tracers in the rest-frame UV/optical. However, galaxies are increasingly obscured by dust emission at higher stellar masses ( 10^10 Msun) and star-formation rates ( 50 Msun/year), such that UV/optical-inferred SFRs can be underestimated by factors of 10-100x. The goal of this proposal is to use all of the collective FIR through millimeter data in a newly developed backward evolution model to: (1) statistically constrain the total integrated IR galaxy luminosity function out to high-redshifts, (2) measure the AGN contribution to the total cosmic infrared background, (3) provide non-clustered predictions for submm source multiplicity, and (4) use simulations to motivate future large (sub)mm surveys for optimization at high-redshifts. This project will draw in undergraduate research scholars from under-represented backgrounds to UT Austin for the summer to conduct research on this topic through the TAURUS program. TAURUS focuses on the long-term retention of highly-motivated under-represented students in STEM careers.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.

哈勃太空望远镜的深空图像揭示了宇宙中最遥远的星系。这些物体是由数千到数百万颗恒星组成的群，就像我们的太阳一样。它们距离我们如此遥远，以至于它们的恒星发出的光需要数十亿年才能到达我们。在哈勃望远镜最深处的图像中可以看到距离这么远的大多数星系，但不是全部。有些星系含有大量尘埃，使它们更难以观测，因为尘埃遮挡了星光。星光加热尘埃，然后尘埃以毫米波长重新辐射能量。这些尘埃星系非常迅速地形成恒星，对于我们了解恒星如何形成非常重要。人们对大爆炸后最初几十亿年中尘埃星系的普遍程度知之甚少。该项目将使用毫米波长的所有可用数据来估计它们在早期的普遍程度。这对于我们对第一个星系如何形成的基本理解非常重要。该项目还将通过 UT 奥斯汀分校的德克萨斯州天文学本科生研究 (TAURUS) 项目，接待来自少数族裔背景的学生进行天文学研究。该研究计划的目标是留住这些优秀的学生从事 STEM 职业。对宇宙恒星形成历史进行普查是星系演化调查的一个关键目标。然而，迄今为止的测量，特别是在最高红移情况下，几乎完全是根据静止帧紫外/光学中清晰的恒星形成示踪剂确定的。然而，星系越来越被更高恒星质量（10^10 兆太阳）和恒星形成速率（50 兆太阳/年）的尘埃排放所遮蔽，使得紫外/光学推断的恒星形成率可能被低估 10-100 倍。该提案的目标是在新开发的后向演化模型中使用所有通过毫米级的集体 FIR 数据：(1) 在统计上将总集成红外星系光度函数限制为高红移，(2) 测量 AGN 对总宇宙红外背景的贡献，(3) 提供亚毫米源多重性的非聚类预测，以及 (4) 使用模拟来激励未来的大型（亚）毫米 高红移优化调查。该项目将吸引来自弱势群体的本科生研究学者在暑假到德州大学奥斯汀分校通过 TAURUS 项目开展该主题的研究。 TAURUS 致力于长期保留 STEM 职业中积极性较低的学生。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力优点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 the Volume Density of Dusty Star-forming Galaxies through the First 3 mm Number Counts from ALMA

• DOI: 10.3847/1538-4357/aaecd2
• 发表时间: 2018-10
• 期刊: The Astrophysical Journal
• 作者: J. Zavala;C. Casey;E. D. Cunha;J. Spilker;J. Staguhn;J. Hodge;P. Drew

The Evolution of the IR Luminosity Function and Dust-obscured Star Formation over the Past 13 Billion Years

• DOI: 10.3847/1538-4357/abdb27
• 发表时间: 2021-01
• 期刊: The Astrophysical Journal
• 作者: J. Zavala;C. Casey;S. Manning;M. Aravena;M. Béthermin;K. Caputi;D. Clements;E. D. Cunha;P. Drew;S. Finkelstein;S. Fujimoto;C. Hayward;J. Hodge;J. Kartaltepe;K. Knudsen;A. Koekemoer;A. Long;G. Magdis;A. Man;G. Popping;D. Sanders;N. Scoville;K. Sheth;J. Staguhn;S. Toft;E. Treister;J. Vieira;M. Yun

Characterization of Two 2 mm detected Optically Obscured Dusty Star-forming Galaxies

• DOI: 10.3847/1538-4357/ac366a
• 发表时间: 2021-11
• 期刊: The Astrophysical Journal
• 作者: S. Manning;C. Casey;J. Zavala;G. Magdis;P. Drew;J. Champagne;M. Aravena;M. Béthermin;D. Clements;S. Finkelstein;S. Fujimoto;C. Hayward;J. Hodge;O. Ilbert;J. Kartaltepe;K. Knudsen;A. Koekemoer;A. Man;D. Sanders;K. Sheth;J. Spilker;J. Staguhn;M. Talia;E. Treister;M. Yun

Mapping Obscuration to Reionization with ALMA (MORA): 2 mm Efficiently Selects the Highest-redshift Obscured Galaxies

• DOI: 10.3847/1538-4357/ac2eb4
• 发表时间: 2021-10
• 期刊: The Astrophysical Journal
• 作者: C. Casey;J. Zavala;S. Manning;M. Aravena;M. Béthermin;K. Caputi;J. Champagne;D. Clements;P. Drew;S. Finkelstein;S. Fujimoto;C. Hayward;A. Koekemoer;V. Kokorev;Claudia del P. Lagos;A. Long;G. Magdis;A. Man;I. Mitsuhashi;G. Popping;J. Spilker;J. Staguhn;M. Talia;S. Toft;E. Treister;J. Weaver;M. Yun

Far-infrared Photometric Redshifts: A New Approach to a Highly Uncertain Enterprise

• DOI: 10.3847/1538-4357/aba528
• 发表时间: 2020-07
• 期刊: The Astrophysical Journal
• 作者: C. Casey