论文标题
1D等温C-shock中的阻力不稳定性
The Drag Instability in a 1D Isothermal C-Shock
论文作者
论文摘要
我们研究了Gu等人提出的阻力不稳定性是否发生在一维（1D）C-shock中。采用了Chen和Ostriker提出的为稳定的等温C震盘提出的一维背景模型，并进行了1D等热线性分析。我们确认了Gu等人的假设。离子和中性之间的漂移速度在C震动中足够高，以实现阻力不稳定性。我们还研究了冲击和震后区域中衰减模式的潜在物理。阻力不稳定性是与传播波的指数生长模式相关的过于稳定现象。我们发现，生长波模式只能在冲击中传播下游，然后在后震后区域腐烂。在这种不稳定波的潮湿之前，在恒星形成云的典型环境中估算了这种不稳定波的最大总生长（MTG），该环境比适度的电击速度的初始扰动大约比初始扰动大约10-30倍，并且可以显着增强数百倍的较高的Chock，具有较大的C骨。
We investigate whether the drag instability, proposed by Gu et al., occurs in a one-dimensional (1D) C-shock. The 1D background model proposed by Chen and Ostriker for a steady isothermal C-shock is adopted, and a 1D isothermal linear analysis is performed. We confirm the postulation of Gu et al. that the drift velocity between the ions and the neutrals is sufficiently high within a C-shock to allow for the drag instability. We also study the underlying physics of the decaying modes in the shock and post-shock regions. The drag instability is an overstability phenomenon associated with an exponentially growing mode of a propagating wave. We find that the growing wave mode can only propagate downstream within the shock and subsequently decay in the post-shock region. The maximum total growth (MTG) for such an unstable wave before it is damped is estimated in typical environments of star-forming clouds, which is approximately 10-30 times larger than the initial perturbation at the modest shock velocities and can be significantly enhanced several hundred times for a stronger C-shock with a larger width.
