New Vistas in Weak Lensing

弱透镜的新景象

• 批准号: 1909193
• 负责人: Rupert Croft
• 金额: $ 64.85万
• 依托单位: Carnegie-Mellon University
• 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 2023-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1909193&HistoricalAwards=false
• 关键词: New; Vistas; Weak; Lensing

Light rays are bent by gravity as they move past massive objects, in a way that was first predicted by Einstein. When astronomical objects are massive enough, such as whole galaxies, then the light bends enough that it can be brought to a focus, creating what is known as a "gravitational lens". Since Einstein's prediction, the study of gravitational lensing has grown enormously, and indeed gravitational lensing is one of the main reasons that we know that "dark matter" exists. Even though all light is affected in this way, so far only two sources of light have ever been used to study gravitational lensing: light from individual galaxies, and the left over light from the Big Bang, known as the Cosmic Microwave Background (CMB). This project will greatly increase the domain over which gravitational lensing is studied. In particular it will add three different new lensed fields to the two currently observed. These are (1) clouds of gas in intergalactic space (which we can view in three dimensions), (2) groups and clusters of galaxies, and (3) the field of time delays measured from CMB light seen in different directions on the sky. The last one, CMB time delay, is caused by the fact that light slows down as it passes through a gravitational lens, so that light arrives at an observer later when a lens is between them and the edge of the observable universe (where the CMB originates). The project aims to lead to an understanding of the theory behind these new fields, how best to measure the lensing effects and how to use them to make accurate maps of the dark matter in the Universe. These concepts, related to the length scales and contents of the cosmos will also be spread by the project to elementary through high school students. This will be done with educational video games, including development of "Minecraft" astronomy lesson plans, and explorable computer models of quasars and intergalactic space and the chemical constituents of the Universe.Weak gravitational lensing is arguably the best way to map out the dark side of the Universe. Billion dollar class surveys and satellites will use distortions of galaxy shapes (galaxy shear) caused by lensing to do this. The more recent adoption of lensing of the Cosmic Microwave Background (CMB) as a cosmological probe has shown the advantages of a different tracer of lensing distortions, with different strengths and systematic errors. These observations of weak lensing are only the beginning, however - any background light sources will undergo the same distortions and there is a rich phenomenology yet to be discovered. The work will expand the use of lensing anisotropies of clustering to three new areas, the Lyman-alpha forest, the galaxy correlation function, and CMB time delay. None relies on measurement of galaxy shapes which can make precise galaxy shear determinations difficult, but two can be measured to high significance with current data and one has potential implications for future surveys. The PI and Co-I have developed some of the first ideas on these topics, and the time is ripe for a concerted effort to unlock their full potential. The project will formulate estimators to derive lens parameters from raw data, and make use of realistic simulated datasets to test and develop them in the presence of non-linearities and non-Gaussianity. These estimators will be applied to data from surveys of the intergalactic medium and the distribution of galaxies. Statistical errors on the matter fluctuation amplitude at the few percent level are expected, but the true gains will be in the differing systematic errors to shear and the new ways the data can probe cosmology. These techniques will offer a new route to measuring the neutrino mass and the evolution of structure.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.

当光线经过大质量物体时，会被重力弯曲，这种弯曲的方式最早是由爱因斯坦预测的。当天文物体足够大时，比如整个星系，那么光线就会弯曲到足以聚焦，形成所谓的“引力透镜”。自从爱因斯坦的预言以来，对引力透镜的研究得到了极大的发展，事实上，引力透镜是我们知道“暗物质”存在的主要原因之一。尽管所有的光都以这种方式受到影响，但迄今为止，只有两种光源被用于研究引力透镜效应：来自单个星系的光，以及大爆炸遗留下来的光，即宇宙微波背景（CMB）。这个项目将大大增加引力透镜研究的范围。特别是，它将在目前观察到的两个透镜场的基础上增加三个不同的新透镜场。这些是(1)星系间空间的气体云（我们可以在三维空间中观察），(2)星系群和星系团，(3)从天空中不同方向观测到的CMB光测量到的时间延迟场。最后一个原因是CMB的时间延迟，这是由于光线在穿过引力透镜时减慢了速度，因此当透镜在观察者和可观测宇宙的边缘（CMB的起源）之间时，光线会晚一些到达观察者。该项目旨在引导人们理解这些新领域背后的理论，如何最好地测量透镜效应，以及如何利用它们来绘制宇宙中暗物质的精确地图。这些与宇宙的长度尺度和内容有关的概念也将通过该项目传播给小学到高中的学生。这将通过教育视频游戏来完成，包括开发“我的世界”天文学课程计划，以及类星体、星系间空间和宇宙化学成分的可探索计算机模型。弱引力透镜效应可以说是绘制宇宙黑暗面的最佳方法。耗资数十亿美元的巡天和卫星将利用透镜效应引起的星系形状扭曲（星系剪切）来做到这一点。最近采用宇宙微波背景（CMB）的透镜作为宇宙探测器，显示了不同的透镜畸变示踪剂的优势，具有不同的强度和系统误差。然而，这些弱透镜现象的观察仅仅是开始，任何背景光源都会经历同样的扭曲，而且还有丰富的现象有待发现。这项工作将把聚类的透镜各向异性扩展到三个新的领域，Lyman-alpha森林，星系相关函数和CMB时间延迟。没有一个依赖于星系形状的测量，这使得精确的星系剪切测定变得困难，但是两个可以用当前的数据测量到很高的意义，一个对未来的调查有潜在的影响。PI和Co-I已经就这些主题提出了一些初步想法，现在时机已经成熟，可以共同努力，充分释放它们的潜力。该项目将制定估算器，从原始数据中推导透镜参数，并利用现实的模拟数据集在非线性和非高斯性存在的情况下进行测试和开发。这些估计器将应用于星系间介质和星系分布的调查数据。预计物质波动幅度的统计误差在几个百分点的水平上，但真正的收获将是不同的系统误差来剪切和数据可以探索宇宙学的新方法。这些技术将为测量中微子的质量和结构演化提供一条新的途径。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

Dark Energy Survey Year 3 results: Exploiting small-scale information with lensing shear ratios

暗能量调查第三年结果：利用透镜剪切比的小规模信息

• DOI: 10.1103/physrevd.105.083529
• 发表时间: 2022
• 期刊: Physical Review D
• 影响因子: 5
• 作者: Sánchez, C.;Prat, J.;Zacharegkas, G.;Pandey, S.;Baxter, E.;Bernstein, G. M.;Blazek, J.;Cawthon, R.;Chang, C.;Krause, E.
• 通讯作者: Krause, E.

Dark Energy Survey Year 1 results: constraints on intrinsic alignments and their colour dependence from galaxy clustering and weak lensing

• DOI: 10.1093/mnras/stz2197
• 发表时间: 2018-11
• 期刊: Monthly Notices of the Royal Astronomical Society
• 影响因子: 4.8
• 作者: S. Samuroff;J. Blazek;M. Troxel;N. MacCrann;E. Krause;C. D. Leonard;J. Prat;D. Gruen;S. Dodelson;T. Eifler;M. Gatti;W. Hartley;B. Hoyle;P. Larsen;J. Zuntz;T. Abbott;S. Allam;J. Annis;G. Bernstein;E. Bertin;S. Bridle;D. Brooks;A. Rosell;M. Kind;J. Carretero;F. Castander;C. Cunha;L. Costa;C. Davis;J. Vicente;D. Depoy;S. Desai;H. Diehl;J. Dietrich;P. Doel;B. Flaugher;P. Fosalba;J. Frieman;J. Garc'ia-Bellido;E. Gaztañaga;D. Gerdes;R. Gruendl;J. Gschwend;G. Gutiérrez;D. Hollowood;K. Honscheid;D. James;K. Kuehn;N. Kuropatkin;M. Lima;M. Maia;M. March;J. Marshall;P. Martini;Peter Melchior;F. Menanteau;C. Miller;R. Miquel;R. Ogando;A. Plazas;E. Sánchez;V. Scarpine;R. Schindler;M. Schubnell;S. Serrano;I. Sevilla-Noarbe;E. Sheldon;M. Smith;F. Sobreira;E. Suchyta;G. Tarlé;D. Thomas;V. Vikram

Data compression and covariance matrix inspection: Cosmic shear

数据压缩和协方差矩阵检查：宇宙剪切

• DOI: 10.1103/physrevd.103.103535
• 发表时间: 2021
• 期刊: Physical Review D
• 影响因子: 5
• 作者: Ferreira, Tassia;Zhang, Tianqing;Chen, Nianyi;Dodelson, Scott
• 通讯作者: Dodelson, Scott

Dark Energy Survey Year 3 results: Cosmology from cosmic shear and robustness to modeling uncertainty

• DOI: 10.1103/physrevd.105.023515
• 发表时间: 2021-05
• 期刊: Physical Review D
• 影响因子: 5
• 作者: L. Secco;S. Samuroff;E. Krause;B. Jain;J. Blazek;M. Raveri;A. Campos;A. Amon;A. Chen;C. Doux;A. Choi;D. Gruen;G. Bernstein;C. Chang;J. DeRose;J. Myles;A. Fert'e;P. Lemos;D. Huterer;J. Prat;M. Troxel;N. MacCrann;A. Liddle;T. Kacprzak;X. Fang;C. S'anchez;S. Pandey;S. Dodelson;P. Chintalapati;K. Hoffmann;A. Alarcon;O. Alves;F. Andrade-Oliveira;E. Baxter;K. Bechtol;M. Becker;A. Brandao-Souza;H. Camacho;A. Rosell;M. Kind;R. Cawthon;J. Cordero;M. Crocce;C. Davis;E. D. Valentino;A. Drlica-Wagner;K. Eckert;T. Eifler;M. Elidaiana;F. Elsner;J. Elvin-Poole;S. Everett;P. Fosalba;O. Friedrich;M. Gatti;G. Giannini;R. Gruendl;I. Harrison;W. Hartley;K. Herner;H. Huang;E. Huff;M. Jarvis;N. Jeffrey;N. Kuropatkin;P. Léget;J. Muir;J. Mccullough;A. Alsina;Y. Omori;Y. Park;A. Porredon;R. Rollins;A. Roodman;R. Rosenfeld;A. Ross;E. Rykoff;J. Sánchez;I. Sevilla-Noarbe;E. Sheldon;T. Shin;I. Tutusaus;T. Varga;N. Weaverdyck;R. Wechsler;B. Yanny;Biao Yin;Y. Zhang;J. Zuntz;T. Abbott;M. Aguena;S. Allam;J. Annis;D. Bacon;E. Bertin;S. Bhargava;S. Bridle;D. Brooks;E. Buckley-Geer;D. Burke;J. Carretero;M. Costanzi;L. Costa;J. Vicente;H. Diehl;J. Dietrich;P. Doel;I. Ferrero;B. Flaugher;J. Frieman;J. Garc'ia-Bellido;E. Gaztañaga;D. Gerdes;T. Giannantonio;J. Gschwend;G. Gutiérrez;S. Hinton;D. Hollowood;K. Honscheid;B. Hoyle;D. James;T. Jeltema;K. Kuehn;O. Lahav;M. Lima;H. Lin;M. Maia;J. Marshall;P. Martini;Peter Melchior;F. Menanteau;R. Miquel;J. Mohr;R. Morgan;R. Ogando;A. Palmese;F. Paz-Chinch'on;D. Petravick;A. Pieres;A. P. Malag'on;M. Rodríguez-Monroy;A. Romer;E. Sánchez;V. Scarpine;M. Schubnell;D. Scolnic;S. Serrano;M. Smith;M. Soares-Santos;E. Suchyta;M. Swanson;G. Tarlé;D. Thomas;C. To

Dark energy survey year 3 results: High-precision measurement and modeling of galaxy-galaxy lensing

暗能量调查第三年结果：星系-星系透镜效应的高精度测量和建模

• DOI: 10.1103/physrevd.105.083528
• 发表时间: 2022
• 期刊: Physical Review D
• 影响因子: 5
• 作者: Prat, J.;Blazek, J.;Sánchez, C.;Tutusaus, I.;Pandey, S.;Elvin-Poole, J.;Krause, E.;Troxel, M. A.;Secco, L. F.;Amon, A.
• 通讯作者: Amon, A.