Studying the Threshold of Galaxy Formation with Ultra-Faint Galaxies

银河系被数十个“超微弱”的卫星星系所包围。对这些星系的观测为我们了解星系如何形成和演化提供了信息。然而，超暗星系很难探测，研究也很有挑战性。研究人员将使用天文成像数据对本地宇宙中的超微弱卫星星系进行普查。这些观测结果将与预测进行比较，以提供对星系形成及其所居住的暗物质晕性质的新见解。该项目将使公众更容易获得最新的天文数据。此外，研究人员将通过公民科学项目吸引公众参与，并培训下一代科学家。研究人员将使用DECam本地体积探测（DELVE）调查的多波段成像数据，对银河系周围的超暗星系、麦哲伦云和本地体积中的麦哲伦类似星系进行严格的统计普查。通过将观测到的卫星群、观测选择函数和宇宙学模拟结合在一个统一的框架中，将有可能在最小的可达尺度上测量暗物质晕和星系之间的关系。这些观测将为宇宙学和星系形成的标准模型提供一个强有力的测试，在以前无法进入的制度。作为该项目的一部分，开发的工具和专业知识将与NSF的Vera C.该奖项反映了NSF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。

The Milky Way is surrounded by dozens of “ultra-faint” satellite galaxies. Observations of these galaxies inform our understanding of how galaxies form and evolve. However, ultra-faint galaxies are difficult to detect and challenging to study. The investigators will use astronomical imaging data to perform a census of ultra-faint satellite galaxies in the local Universe. These observations will be compared to predictions to provide new insights into the formation of galaxies and the nature of the dark matter halos that they inhabit. This project will enhance public access to state-of-the art astronomical data. Furthermore, the investigators will engage the public through citizen science projects and train the next generation of scientists.The investigators will use multi-band imaging data from the DECam Local Volume Exploration (DELVE) survey to perform a statistically rigorous census of ultra-faint galaxies around the Milky Way, the Magellanic Clouds, and Magellanic-analog galaxies in the Local Volume. By combining observed satellite populations, observational selection functions, and cosmological simulations in a unified framework, it will be possible to measure the relationship between dark matter halos and galaxies at the smallest accessible scales. These observations will provide a powerful test of the standard model of cosmology and galaxy formation in a previously inaccessible regime. The tools and expertise that are developed as part of this project will enhance early science with the NSF’s Vera C. Rubin Observatory.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.