Collaborative Research: Magellanic dwarfs as a key laboratory for dwarf galaxy formation

标准的宇宙学暗物质（DM）方案预测，所有星系都被各种形状的DM包围。 研究人员试图了解矮星系中星星的形成过程，这受到这些超暗星系周围DM结构形状的影响。大麦哲伦云（LMC）是绕银河系运行的最重要的矮星系，过去几年发现的许多新的超暗星系都是在大麦哲伦云附近发现的。研究人员将对矮星系的形成进行数值模拟，并将他们的模型预测与。这项研究将涉及两个机构的学生，他们将协助研究并学习计算机编程技能。研究人员将生成和分析来自FIRE项目的新的超高分辨率宇宙学放大流体动力学模拟，以研究5个LMC样晕的形成和演化，对不同的组装历史和宇宙学散射进行采样。通过了解LMC和LMC类星系的卫星群，研究人员将在最小尺度上限制星系形成的物理学。 该团队将在再电离时间，早期宇宙星星形成和增加分辨率方面进行几种变化，以研究它们对当今超微弱卫星预测数量的影响。这一努力将把一套高分辨率的放大模拟扩展到星系形成的最低质量区域。研究人员解决了3个基本问题：（1）LMC类星系周围超微弱卫星星系的数量和质量;（2）超微弱矮星系的恒星形成历史以及内部（例如恒星反馈）与外部（例如再电离，环境效应）过程的影响;以及（3）LMC质量星系周围预期的恒星晕成分。该奖项反映了NSF的法定使命，并被认为是值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估的支持。

The standard cosmological Dark Matter (DM) scenario predicts that all galaxies are surrounded by DM in a variety of shapes. The investigators seek to understand star formation processes in dwarf galaxies, which is influenced by the shape of DM structures around these ultra-faint galaxies. The Large Magellanic Cloud (LMC) is the most important dwarf galaxy that orbits our Milky Way, and many of the discoveries of new ultra-faint galaxies over the last few years have been near the LMC. The investigators will numerically model the formation of dwarf galaxies, and they will compare their model predictions to. This research will involve students at both institutions, who will assist in the research and learn computer programming skills. The investigators will generate and analyze new ultra-high-resolution cosmological zoom-in hydrodynamical simulations from the FIRE project to study the formation and evolution of 5 LMC-like halos, to sample different assembly histories and cosmological scatter. By understanding the satellite population of the LMC and LMC-like galaxies, the investigators will constrain the physics of galaxy formation at the smallest scales. The team will run several variations in reionization time, early-universe star formation, and increased resolution, to study their impact on the predicted population of ultra-faint satellites today. This effort will extend the suite of high-resolution zoom-in simulations into the lowest-mass regime of galaxy formation. The investigators address 3 fundamental questions: (1) the counts and masses of ultra-faint satellite galaxies around LMC-like galaxies; (2) the star-formation histories of ultra-faint dwarf galaxies and the impact of internal (e.g. stellar feedback) versus external (e.g. reionization, environmental effects) processes; and (3) the expected stellar halo component around LMC-mass galaxies. They will involve undergraduates from underrepresented groups in their research.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.