标题： 模拟银河盘模型中的恒星形成和反馈 显示英文标题

标题： Simulating Star Formation and Feedback in Galactic Disk Models

摘要： 我们使用基于高分辨率网格的流体力学方法来模拟一个与银河系大小相当的平静盘状星系中的多相星际介质。模型是全局性的和三维的，并且包括恒星形成和反馈的处理。我们研究了引力不稳定性的形成，并表明Toomre不稳定性判据的一种形式可以成功预测恒星形成的出现位置。调查了两种常见的恒星形成方案。第一种基于宇宙学模拟，具有相对较低的恒星形成阈值，但同时也强制实施了较低的效率。第二种仅允许在大于1000 cm⁻³的数密度下发生恒星形成，但采用较高的效率。我们展示了这两种方法都能够重现恒星形成与气体面密度之间关系的观测斜率（尽管对于我们的参数设置，速率过高）。包括II型超新星反馈的运行成功地驱使气体离开平面，其中大部分又回落到盘面上。这种反馈还大大减少了恒星形成率。最后，我们检查了星际介质的密度和压力分布，并显示盘中有大致的压力平衡，但在特定位置存在广泛的压力范围（即使更广的是包括反馈的情况）。 显示英文摘要

摘要： We use a high-resolution grid-based hydrodynamics method to simulate the multi-phase interstellar medium in a Milky Way-size quiescent disk galaxy. The models are global and three-dimensional, and include a treatment of star formation and feedback. We examine the formation of gravitational instabilities and show that a form of the Toomre instability criterion can successfully predict where star formation will occur. Two common prescriptions for star formation are investigated. The first is based on cosmological simulations and has a relatively low threshold for star formation, but also enforces a comparatively low efficiency. The second only permits star formation above a number density of 1000 cm^-3 but adopts a high efficiency. We show that both methods can reproduce the observed slope of the relationship between star formation and gas surface density (although at too high a rate for our adopted parameters). A run which includes feedback from type II supernovae is successful at driving gas out of the plane, most of which falls back onto the disk. This feedback also substantially reduces the star formation rate. Finally, we examine the density and pressure distribution of the ISM, and show that there is a rough pressure equilibrium in the disk, but with a wide range of pressures at a given location (and even wider for the case including feedback