Toward an Accurate Model for the Gas Around Galaxies

对附近星系的观察表明，这些星系仍在增长，因为它们周围的气体云落进了这些星系。到目前为止，星系生长和恒星形成的模型并不能完全解释观测结果。研究人员将对流入的气体的物理性质进行更精细的建模。研究人员强烈认为，更好的数值模型将解释这种差异。环绕星系的低密度气体--环星系介质(CGM)，因其在星系中形成新一代恒星的复杂过程中的关键作用而日益得到认可。对CGM的观测表明，星系周围存在大量气体。然而，理论家无法解释为什么这种气体存在如此大的丰度，因为目前的计算机模型严重低估了它。最近的发现表明，传统的模拟无法解决小的冷气云，这可能解释了理论和观测之间的不匹配。研究人员现在正在运行最先进的模拟，明确跟踪冷气体成分。在这项研究中，他们将对我们的模拟和CGM的许多观测结果进行新颖的比较。研究人员将利用这些观察结果来推断他们的模型在解释CGM的难以捉摸的行为及其对星系生长的影响方面有多准确。传统上，科学机构开展的公众教育努力将目标受众偏向已经对科学感到兴奋的人，而忽略了社区的大部分其他人。调查员的团队在公园、步行街、公共交通、酒吧等非传统场所组织公众教育活动，以真正接触到我们社会的广泛阶层，包括STEM中代表性不足的群体。调查人员将通过设计和建造“AstroViz”工具包来扩展现有的外联工作，该工具包能够在这些非传统的公共教育活动中投射最先进的计算模拟。这些投影将采用先进的可视化技术，使公众能够快速掌握仅通过文字难以传达的概念。应用于附近的人行道或店面，调查人员投影的可视化将更好地吸引公众的注意。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。

Observations of nearby galaxies show that these galaxies are still growing, as gas clouds surrounding them fall into these galaxies. So far, models of how galaxies grow, and stars form, do not fully explain the observations. The investigators will more finely model the physical properties of the infalling gas. The investigators have strongly argued that better numerical models will explain the discrepancies.The circumgalactic medium (CGM), the low-density gas surrounding galaxies, is increasingly recognized for its crucial role in the complicated process of forming new generations of stars in galaxies. Observations of the CGM indicate large quantities gas are present around galaxies. However, theorists cannot explain why that gas exists in such large abundances, because current computer models severely underpredict it. Recent discoveries indicate that traditional simulations fail to resolve small cool gas clouds, potentially explaining the mismatch between theory and observation. The investigators are now running state-of-the-art simulations which track the cool gas component explicitly. In this study, they will make novel comparisons between our simulations and many observations of the CGM. The investigators will use the observations to deduce how accurate their models are at explaining the elusive behavior of the CGM and its effects on galaxy growth.Traditionally, public education efforts held in scientific institutions bias target audiences towards people already excited about science, while ignoring much of the rest of the community. The investigator's team organizes public education activities in non-traditional venues like parks, pedestrian streets, public transportation, bars, etc. to truly reach a wide cross-section of our society, including underrepresented groups in STEM. The investigators will extend existing outreach efforts by designing and building an "AstroViz" kit, capable of projecting state-of-the-art computational simulations at these non-traditional public education events. These projections will employ the advanced visualizations that enable the public to quickly grasp concepts not easily conveyed through words alone. Applied to a nearby sidewalk or storefront, the investigators projected visualizations will better draw the attention of the public.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.