Probing the Universe's expansion and gravitational wave sources with ground-based optical telescopes

用地面光学望远镜探测宇宙的膨胀和引力波源

• 批准号: 2308193
• 负责人: Antonella Palmese
• 金额: $ 46.59万
• 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: 2023
• 资助国家: 美国
• 起止时间: 2023-08-01 至 2026-07-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2308193&HistoricalAwards=false
• 关键词: Probing; Universe; expansion; gravitational; wave

A research team at Carnegie-Mellon University will carry out an observational campaign of astronomical transient events using primarily the Dark Energy Camera (DECam), with a focus on the gravitational wave (GW) sources that will be detected in the upcoming LIGO/Virgo/KAGRA GW detectors observing run (expected during 2023-2024). So far, only one electromagnetic (EM) counterpart to a GW binary neutron star merger has been confidently identified. The goal of the project is to discover new electromagnetic counterparts to mergers of binary neutron stars, while also searching for the first optical transient events associated with GW neutron star-black hole mergers and massive stellar binary black holes. The team will make use of a state-of-the-art difference imaging software pipeline, and machine learning methods to identify transients and model their light curves. Finally, this program will use the DECam observations, in combination with spectroscopic data from other ground-based facilities and GW data, to study the environment of GW sources to understand the origin of gravitational wave sources, and to produce new measurements of the Hubble constant H0, a measure of the expansion rate of the universe, through a procedure called the standard siren method. As part of this program, the team will provide tutorials based on the new DECam data at local public high schools through the Teachers Training program, and providing outreach to the broader community through public lectures and articles.DECam is one of the very few currently functioning instruments with the capabilities to enable EM counterpart discoveries in the upcoming GW observing run. This project, therefore, serves an important role within the multi-messenger astronomy community. EM counterpart discoveries enable a wide range of scientific analyses that are otherwise inconclusive or impossible with GW data alone. These include constraining (1) the equation of state of neutron stars, (2) modifications to General Relativity, and (3) the production of the heaviest elements in the Universe. This project focuses on addressing two pressing questions in astrophysics: the puzzling “Hubble constant tension”, a discrepancy between values of H0 measured through different probes, and the origin of merging binary systems, whether facilitated by dynamical interactions or by stellar evolution. This award advances the goals of the Windows on the Universe Big Idea.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.

卡内基-梅隆大学的一个研究小组将主要使用暗能量相机(DECAM)对天文瞬变事件进行观测，重点放在即将到来的LIGO/Virgo/KAGRA GW探测器观测运行(预计在2023-2024年期间)中探测到的引力波(GW)源。到目前为止，只有一个电磁(EM)对应物被确定为GW双中子星合并。该项目的目标是发现双星中子星合并的新电磁对应物，同时还搜索与GW中子星-黑洞合并和大质量恒星双星黑洞相关的第一个光学瞬变事件。该团队将利用最先进的差分成像软件管道和机器学习方法来识别瞬变并对其光曲线进行建模。最后，该计划将使用DECAM观测，结合来自其他地面设施的光谱数据和GW数据，研究GW源的环境，以了解引力波源的来源，并通过一种称为标准警报器的程序产生新的哈勃常数H0测量结果，H0是一种测量宇宙膨胀率的方法。作为该计划的一部分，该团队将通过教师培训计划在当地公立高中提供基于新的DECAM数据的教程，并通过公开讲座和文章向更广泛的社区提供推广。DECAM是目前极少数能够在即将到来的GW观测运行中实现EM对等发现的工具之一。因此，该项目在多信使天文学社区中发挥着重要作用。EM的对应发现使广泛的科学分析成为可能，否则仅凭GW数据是不确定的或不可能的。这些约束包括(1)中子星的状态方程，(2)对广义相对论的修正，以及(3)宇宙中最重元素的产生。这个项目专注于解决天体物理学中两个紧迫的问题：令人费解的“哈勃常量张力”，通过不同探测器测量的H0值之间的差异，以及双星系统合并的起源，无论是由动力相互作用还是恒星演化促成的。这一奖项推进了宇宙大理想之窗的目标。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。