Collaborative Research: CDS&E: FIRE: Physically-Predictive Cosmological Simulations of Galaxy Formation with Resolved Feedback

“现实环境中的反馈”（FIRE）项目引入了令人兴奋的新方法来解释宇宙年轻时形成的最早一代恒星对星系和星系团形成的影响，宇宙学的大规模示踪剂，宇宙起源和演化的科学。FIRE计算机模型将包含比以往任何时候都多的重要物理学，早期的测试表明，这项工作比以前的研究更符合观察结果，以前的研究必须包括各种任意假设才能取得进展。FIRE中的技术细节还将把星系形成的不确定物理现象与仅仅由计算机建模的局限性引起的问题分开。FIRE将使用高分辨率宇宙学模拟对星系形成进行新颖的计算研究，以前所未有的真实感解决星际介质（ISM）。恒星的形成将大量的能量和动量注入到周围的介质中，这种恒星反馈产生了影响星系环境的星系风。这个项目将运行第一个自洽的宇宙学模拟，包括重要的恒星反馈物理。将已解决的多相ISM与高度非线性反馈相互作用相结合，产生了与观测结果广泛一致的强大星系风，而无需使用以往模拟必须调用的任何临时处方。FIRE模拟将通过恒星反馈、星系流入和流出的特性、星系的形态转变、大质量星系中恒星形成的淬火、活动星系核反馈、电离光子的逃逸分数以及暗物质晕的恒星反馈来解决星系生长的调节问题。所有这些模拟都将与多波长观测直接联系起来。特别是，与高红移测量相比较的模拟吸收线统计数据将检验星系内外气体流动的预测。纳入FIRE的技术改进将有助于量化星系形成模型中数值和物理不确定性的相对重要性。所有FIRE模拟的初始条件将向社区提供，以激励其他人遵循这种方法。该项目包括培训四名研究生，他们也将从三个机构的合作互动中学习。FIRE的可视化为面向高中学生的推广提供了基础，包括为教师举办的计算思维研讨会。其他努力包括针对教师、当地天文爱好者和来自代表性不足群体的学生的研讨会，努力解释地球上当地现象与FIRE研究的宇宙过程之间的联系。

The "Feedback in Realistic Environments" (FIRE) project introduces exciting new ways to account for the effects of the earliest generation of stars, formed when the Universe is young, on the formation of galaxies and clusters of galaxies, the large-scale tracers of cosmology, the science of the origin and evolution of the Universe. The FIRE computer models will include more of the important physics than has ever been done before, and early tests suggest this work agrees with observations more cleanly than previous studies, which had to include various arbitrary assumptions in order to make progress. The technical details within FIRE will also disentangle problems due to the uncertain physics of galaxy formation from problems caused solely by the limitations of computer modeling.FIRE will carry out novel computational studies of galaxy formation using high-resolution cosmological simulations that resolve the interstellar medium (ISM) with unprecedented realism. Star formation injects large quantities of energy and momentum into the surrounding medium, and this stellar feedback generates galactic winds that affect the galactic environment. This project will run the first cosmological simulations that self-consistently include important stellar feedback physics. Combining a resolved, multiphase ISM with highly non-linear feedback interactions produces powerful galactic winds in broad agreement with observations, without using any of the ad hoc prescriptions which previous simulations have had to invoke. FIRE simulations will address the regulation of galaxy growth by stellar feedback, the properties of galactic inflows and outflows, the morphological transformation of galaxies, quenching of star formation in massive galaxies, active galactic nucleus feedback, the escape fraction of ionizing photons, and stellar feedback on dark matter halos. All of these simulations will be connected directly with multi-wavelength observations. In particular, simulated absorption line statistics compared with high-redshift measurements will test predictions of gas flows in and out of galaxies. Technical enhancements incorporated into FIRE will help to quantify the relative importance of numerical and physical uncertainties in galaxy formation modeling. The initial conditions of all FIRE simulations will be made available to the community to motivate others to follow this approach.The project includes training of four graduate students, who will also learn from the collaborative interactions across three institutions. Visualizations from FIRE form a basis for outreach targeted at high school students, including workshops in computational thinking for teachers. Other efforts include seminars aimed at teachers, local astronomy enthusiasts, and students from underrepresented groups, working to explain the connection between local phenomena on Earth and the cosmic processes studied by FIRE.