发表机构
School of Physics and Astronomy, Sun Yat-Sen University; CSST Science Center for the Guangdong-Hong Kong-Macau Greater Bay Area（中山大学物理学院; 粤港澳大湾区宇宙线科学中心）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
通过优化恒星形成和超新星反馈的次网格模型，在4-32 pc分辨率下显著提高了星暴星系模拟的收敛性，减少了恒星质量和外流性质的数值误差。
AI 中文摘要
星系流体动力学模拟的预测能力常常受到恒星形成（SF）和恒星反馈次网格模型对分辨率依赖性的阻碍。我们展示了在4、8、16、32 pc分辨率下对一个类似M82的低质量星暴星系的二维流体动力学模拟，并开发了优化的次网格方案以缓解这些数值不一致性。对于恒星形成，我们采用约20 pc物理尺度控制体积，对应于巨分子云（GMCs）的典型大小，用于气体吸积到沉降粒子上，从而减少其对数值分辨率的依赖。我们进一步纳入了一个经验性的、分辨率和密度相关的恒星形成方案，该方案考虑了气体面密度随空间尺度的变化，正如观测所建议的那样。此外，我们通过将注入体积锚定到超新星遗迹的物理冷却半径（$R_{\ m cool}$）并利用分辨率相关的热-动能分配，改进了超新星反馈耦合。这些改进显著增强了4至32 pc范围内的收敛性：形成的总恒星质量和动能的变化减少到约20%，而冷相质量外流率和积分X射线光度的相对误差降低到约40%以下。暖相和热相外流相位的收敛性仍然较差，变化分别约为50%和75%。升级后的模型还改善了归一化风属性的收敛性，时间平均质量载荷因子、能量载荷因子和X射线发射效率的相对误差分别低于约50%、约80%和约20%。我们的结果为实现更稳健的星暴星系模拟提供了一个实用框架。
英文摘要
The predictive power of hydrodynamic simulations of galaxies is often hampered by the resolution dependence of sub-grid models for star formation (SF) and stellar feedback. We present three-dimensional hydrodynamic simulations of an M82-like low-mass starburst galaxy at resolutions of 4, 8, 16, 32 pc and develop optimized sub-grid prescriptions to mitigate these numerical inconsistencies. For star formation, we adopt a $\sim20$ pc physical-scale control volume, corresponding to the typical size of giant molecular clouds (GMCs), for gas accretion onto sink particles, reducing its dependence on numerical resolution. We further incorporate an empirical, resolution- and density-dependent star formation scheme that accounts for variations in gas surface density across spatial scales, as suggested by observations. Furthermore, we refine the supernova feedback coupling by anchoring the injection volume to the physical cooling radius of the supernova remnant ($R_{\rm cool}$) and utilizing a resolution-dependent thermal-to-kinetic energy partition. These improvements substantially enhance convergence across 4 to 32 pc: variations in the total stellar mass formed and kinetic energy are reduced to $\sim20\%$, while relative errors in the cool-phase mass outflow rate and integrated X-ray luminosity decrease to below $\sim40\%$. The warm and hot outflow phases remain less well converged, with variations of $\sim50\%$ and $\sim75\%$, respectively. The upgraded model also improves the convergence of normalized wind properties, with relative errors below $\sim50\%$, $\sim80\%$, and $\sim20\%$ for the time-averaged mass loading factor, energy loading factor, and X-ray emission efficiency, respectively. Our results provide a practical framework for achieving more robust simulations of starburst galaxies.
Comments34 pages, 12 figures, Accepted for publication in ApJ
