Title: Radiation Hydrodynamic Simulations of Dust-Driven Winds Show Chinese title

Title: 尘埃驱动风的辐射流体动力学模拟

Abstract: We study dusty winds driven by radiation pressure in the atmosphere of a rapidly star-forming environment. We apply the variable Eddington tensor algorithm to re-examine the two-dimensional radiation hydrodynamic problem of a column of gas that is accelerated by a constant infrared radiation flux. In the absence of gravity, the system is primarily characterized by the initial optical depth of the gas. We perform several runs with different initial optical depth and resolution. We find that the gas spreads out along the vertical direction, as its mean velocity and velocity dispersion increase. In contrast to previous work using flux-limited diffusion algorithm, we find little evolution in the trapping factor. The momentum coupling between radiation and gas in the absence of gravity is similar to that with gravity. For Eddington ratio increasing with the height in the system, the momentum transfer from the radiation to the gas is not merely $\sim L/c$, but amplified by a factor of $1+\eta \tau_{\rm IR}$, where $\tau_{\rm IR}$ is the integrated infrared optical depth through the system, and $\eta\sim0.5-0.9$, decreasing with the optical depth. We apply our results to the atmosphere of galaxies and conclude that radiation pressure may be an important mechanism for driving winds in the most rapidly star-forming galaxies and starbursts. Show Chinese abstract

Abstract: 我们研究了由辐射压驱动的尘埃风，在快速恒星形成环境的大气中。 我们将可变爱丁顿张量算法应用于重新审视一维辐射流体力学问题，该问题涉及一列由恒定红外辐射通量加速的气体。 在没有重力的情况下，系统主要由气体的初始光深度来表征。 我们进行了多次具有不同初始光深度和分辨率的运行。 我们发现，随着平均速度和速度弥散度的增加，气体沿垂直方向扩展。 与之前使用流量限制扩散算法的工作相比，我们发现捕获因子几乎没有演化。 在没有重力的情况下，辐射和气体之间的动量耦合类似于存在重力的情况。 对于爱丁顿比随系统高度增加的情况，从辐射到气体的动量传递不仅仅是$\sim L/c$，而是放大了$1+\eta \tau_{\rm IR}$倍，其中$\tau_{\rm IR}$是系统内积分的红外光深度，而$\eta\sim0.5-0.9$随光深度减小。 我们将我们的结果应用于星系大气，并得出结论，辐射压力可能是推动最快速恒星形成星系和恒星爆发中风的重要机制。