Galactic outflows have density, temperature, and velocity variations at least as large as those of the multiphase, turbulent interstellar medium (ISM) from which they originate. We have conducted a suite of parsec-resolution numerical simulations using the TIGRESS framework, in which outflows emerge as a consequence of interaction between supernovae (SNe) and the star-forming ISM. The outflowing gas is characterized by two distinct thermal phases, cool (T≲10⁴ K) and hot (T≳10⁶ K), with most mass carried by the cool phase and most energy and newly injected metals carried by the hot phase. Both components have a broad distribution of outflow velocity, and especially for cool gas this implies a varying fraction of escaping material depending on the halo potential. Informed by the TIGRESS results, we develop straightforward analytic formulae for the joint probability density functions (PDFs) of mass, momentum, energy, and metal loading as distributions in outflow velocity and sound speed. The model PDFs have only two parameters, star formation rate surface density and the metallicity of the ISM, and fully capture the behavior of the original TIGRESS simulation PDFs over . Employing PDFs from resolved simulations will enable implementations of subgrid models for galaxy formation with wind velocity and temperature (as well as total loading factors) that are based on theoretical predictions rather than empirical tuning. This is a critical step to incorporate advances from TIGRESS and other high-resolution simulations in future cosmological hydrodynamics and semi-analytic galaxy formation models. We release a Python package to prototype our model and to ease its implementation.

银河外流的密度，温度和速度变化至少与其起源的多相湍流星际介质（ISM）一样大。我们已经使用TIGRESS框架进行了一组视差分辨率的数值模拟，其中由于超新星（SNe）与恒星形成的ISM相互作用而出现流出。流出的气体的特征是两个不同的热阶段，冷却（Ť ≲10 ⁴ K）和热（Ť ≳10 ⁶K），其中大部分由冷相承载，大部分能量由新相注入，而热相则承载新注入的金属。两种成分的流出速度分布都很广，尤其是对于冷气体而言，这意味着根据晕轮电位，逸出材料的逸出率各不相同。在TIGRESS结果的通知下，我们为质量，动量，能量和金属负载的联合概率密度函数（PDF），以流出速度和声速的分布，开发了简单的解析公式。模型PDF仅具有两个参数，即恒星形成率表面密度和ISM的金属性，并且可以完全捕获原始TIGRESS仿真PDF在。从解析的模拟中使用PDF可以实现基于理论预测而非经验调整的风速和温度（以及总负荷因子）的星系形成子网格模型。这是将TIGRESS和其他高分辨率模拟技术的进步纳入未来宇宙流体力学和半解析星系形成模型的关键步骤。我们发布了一个Python软件包来对模型进行原型设计并简化其实现。