AI 中文总结
该研究基于阿扎哈尔系列模拟，通过纳入辐射传输、宇宙射线等非热物理，构建非热模型。此模型能再现高红移到宇宙正午的紫外光度函数等，揭示简单热反馈模型不足，表明非热物理对解释高红移星系至关重要。
AI 中文摘要
詹姆斯·韦布空间望远镜（JWST）的观测将星系的发现和特征研究推进到宇宙黎明时期，揭示了当前星系形成模拟存在重大不足，需要新的基于物理的模型。我们展示了阿扎哈尔系列的首批结果，这是十个高分辨率（约20秒差距）、大体积的放大宇宙学模拟，除了“标准”重子物理外，还逐步纳入辐射传输（RT）、宇宙射线（CRs）和磁流体动力学。我们的非热模型同时实时包含RT和CRs，再现了从高红移（z~14）到宇宙正午（z~3）观测到的紫外光度函数，以及恒星质量函数、星系主序和观测到的气体金属丰度的演化。通过更爆发性的恒星形成，在长（gtrsim50 Myr）和短（lesssim10 Myr）时间尺度上增强变异性，以及随着CR压力在星际介质中积累，宇宙时间内流出质量加载因子从高到低的转变来实现。我们发现简单的（增强的）热超新星反馈模型无法捕捉最早星系的宇宙演化，因为它们缺乏在不同时间尺度上运行且具有不同热力学性质的现实反馈通道，从而要么产生过多恒星质量，要么驱动过度爆发的外流。我们的结果表明，非热星系形成物理对于提供一个强大的理论框架来解释JWST现在发现的高红移星系群体至关重要。
英文摘要
JWST observations, which have pushed the discovery and characterization of galaxies to cosmic dawn, have revealed significant deficiencies in state-of-the-art galaxy formation simulations, motivating the need for novel, physically grounded models. We present the first results from the Azahar suite of ten high-resolution ($\sim$20 pc), large-volume zoom-in cosmological simulations, which follow the formation of thousands of galaxies and progressively incorporate radiative transfer (RT), cosmic rays (CRs), and magnetohydrodynamics in addition to the 'standard' baryonic physics. Our Non-Thermal model, which simultaneously includes RT and CRs on the fly, reproduces the observed UV luminosity function from high redshifts ($z \sim 14$) to cosmic noon ($z \sim 3$), as well as the evolution of the stellar mass function, the galaxy main sequence, and observed gas metallicities. It does so through a combination of burstier star formation, with enhanced variability on both long ($\gtrsim 50$ Myr) and short ($\lesssim 10$ Myr) timescales, and a transition from high to low outflow mass-loading factors over cosmic time as CR pressure builds up in the ISM. We find that simple (boosted) thermal SN feedback models fail to capture the cosmic evolution of the very first galaxies because they lack realistic feedback channels that operate on different timescales and have distinct thermodynamical properties, thereby either overproducing stellar mass or driving overly explosive outflows. Our results indicate that non-thermal galaxy formation physics is crucial for providing a robust theoretical framework with which to interpret the high-redshift galaxy populations now being uncovered by JWST.
Comments33 pages (22 in main text), 18 figures (12 in main text), and 6 appendices. Submitted to ApJ. More information and visualizations at https://www.azaharsimulations.com/
