Signatures of peculiar velocities in the cosmic microwave background

宇宙微波背景中奇特速度的特征

• 批准号: 1910678
• 负责人: Elena Pierpaoli
• 金额: $ 37.77万
• 依托单位: University of Southern California
• 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 2022-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1910678&HistoricalAwards=false
• 关键词: Signatures; peculiar; velocities; cosmic; microwave

The statistics of the peculiar velocity field of galaxy clusters (i.e., motions not related to expansion of the universe) are highly informative about the nature of dark matter, dark energy, and the theory of gravity. Currently, peculiar velocity measurements on large scales are limited to only the line-of-sight components of clusters, leaving most of the available information in the velocity field inaccessible to us. The yet-undetected transverse components can be traced through the cosmic microwave background (CMB) via two effects: (i) the Birkinshaw-Gull (BG) effect in CMB temperature, and (ii) the Kinetic Sunyaev-Zeldocivh (kSZ) effect in CMB polarization. In this research, we make a realistic assessment of the detectability of these signals with the near future CMB experiments, and also investigate the possibility of exploiting the statistics of these signals for cosmology. The PI will develop a creative educational product for K-12 students to promote awareness of and interest in physics and cosmology, in particular the physics of galaxy clusters and structure formation. K-12 teachers will be trained to use this educational product leveraging on existing relationships via the USC family of schools. The developed material will also be available online for all educators willing to download and use it. The amplitude of both BG and kSZ effects are subdominant with respect to the primary CMB anisotropies and current instrumental noise levels. Aside from this, the signals can be confused with other emissions from within and outside the clusters, gravitational lensing effects, and uncertainties in clusters' physical description. Therefore, it is almost impossible to observe these effects for individual objects. Nevertheless, it is still possible to achieve a successful detection of them by employing novel statistical methods in the analysis of data. One example is to use pairwise statistical estimators which have been shown to significantly increase the detection signal-to-noise ratio. Throughout this project we will investigate the possibility of measuring these signals in the near future using the next generation of CMB surveys. We will provide forecast analyses through semi-analytical and numerical simulations of clusters and introduce proper map-filtering techniques and new statistical tools for this purpose. The current general interest in producing larger and deeper CMB surveys with improved intensity and polarization sensitivities makes this an appropriate time to further the study of peculiar velocities and inspect their cosmological implications.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.

星系簇的特殊速度场（即与宇宙扩张无关的动议）的统计数据对暗物质，暗能量和重力理论的性质有很高的信息。当前，大尺度上的特殊速度测量仅限于簇的视线组件，而我们在速度字段中的大多数可用信息对我们来说无法访问。 可以通过两种效应通过宇宙微波背景（CMB）追踪尚未实现的横向成分：（i）CMB温度的伯金肖海鸥（BG）效应，以及（ii）CMB极化中的动力学Sunyaev-Zeldocivh（ksz）。在这项研究中，我们通过不久的将来的CMB实验对这些信号的可检测性进行了现实评估，并研究了利用这些信号的统计数据的可能性。 PI将为K-12学生开发一种创造性的教育产品，以促进对物理和宇宙学的意识和兴趣，尤其是星系簇和结构形成的物理学。 K-12教师将接受培训，以利用这种教育产品利用通过USC的学校家族来利用现有关系。开发的材料也将在线提供，所有愿意下载和使用它的教育者。 BG和KSZ效应的幅度相对于主要的CMB各向异性和当前的仪器噪声水平都是亚抑制剂。除此之外，信号还可以与簇内外的其他排放相混淆，重力镜头效应以及簇的物理描述中的不确定性。因此，几乎不可能观察到这些对单个对象的影响。然而，通过在数据分析中采用新颖的统计方法，仍然可以成功地检测它们。一个例子是使用成对的统计估计器，这些估计量已显示出显着增加检测信号噪声比。在整个项目中，我们将使用下一代CMB调查在不久的将来调查这些信号的可能性。我们将通过群集的半分析和数值模拟进行预测分析，并为此引入适当的地图过滤技术和新的统计工具。目前，人们对通过提高强度和两极分化敏感性进行更大和更深入的CMB调查的普遍兴趣使得这是进一步研究特殊速度并检查其宇宙学的含义的适当时机。该奖项反映了NSF的法定任务，并通过使用该基金会的知识优点和广泛的影响来评估NSF的法定任务，并被认为是值得的支持。

项目成果

Footprints of Doppler and aberration effects in cosmic microwave background experiments: statistical and cosmological implications

• DOI: 10.1093/mnras/staa332
• 发表时间: 2019-10
• 期刊: Monthly Notices of the Royal Astronomical Society
• 影响因子: 4.8
• 作者: S. Yasini;E. Pierpaoli

Effects of boosting on extragalactic components: methods and statistical studies

增强对河外成分的影响：方法和统计研究

• DOI: 10.1093/mnras/stac1017
• 发表时间: 2022
• 期刊: Monthly Notices of the Royal Astronomical Society
• 影响因子: 4.8
• 作者: Coulton, William;Feldman, Sydney;Maamari, Karime;Pierpaoli, Elena;Yasini, Siavash;Dolag, Klaus
• 通讯作者: Dolag, Klaus

AstroPaint: A Python Package for Painting Halo Catalogs into Celestial Maps

AstroPaint：用于将 Halo 目录绘制到天体图中的 Python 包

• DOI: 10.21105/joss.02608
• 发表时间: 2020
• 期刊: Journal of Open Source Software
• 作者: Yasini, Siavash;Alvarez, Marcelo;Schaan, Emmanuel;Maamari, Karime;Mazinani, Shobeir;Mirzatuny, Nareg;Pierpaoli, Elena
• 通讯作者: Pierpaoli, Elena