论文标题
扰动的低质量盘形气星I：一般和标准模型中的环形结构
Annular structures in perturbed low mass disc-shaped gaseous nebulae I : general and standard models
论文作者
论文摘要
摘要这是两篇论文中的第一篇，我们研究了二维低质量气态圆盘的分析解决方案，该圆盘缓慢地围绕中央质量旋转并提交给小径向周期性扰动。对于平衡和扰动配置，求解了流体动力学方程。对于不受干扰的特异性质量和声速的功率定律分布的几种指数，推导并求解了气体扰动特异性质量的波状方程。发现首先，气体扰动的特定质量显示呈指数间隔的最大值，对应于径向扰动速度的零。其次，扰动特异性质量的连续最大值的距离比是持续的，具体取决于椎间盘特征，并按照模型，也取决于扰动的频率。第三，从minima的区域诱发了内向和向外气流，朝着扰动的特定质量的最大区域诱导，最终导致盘中可能形成气态环形结构。提出的结果可以在各种天体物理环境中应用于缓慢旋转的相对质量可忽略不计的薄气盘，并提交给小径向周期性扰动。
Abstract This is the first of two papers where we study analytical solutions of a bidimensional low mass gaseous disc slowly rotating around a central mass and submitted to small radial periodic perturbations. Hydrodynamics equations are solved for the equilibrium and perturbed configurations. A wave-like equation for the gas perturbed specific mass is deduced and solved analytically for several cases of exponents of the power law distributions of the unperturbed specific mass and sound speed. It is found that, first, the gas perturbed specific mass displays exponentially spaced maxima, corresponding to zeros of the radial perturbed velocity; second, the distance ratio of successive maxima of the perturbed specific mass is a constant depending on disc characteristics and, following the model, also on the perturbation's frequency; and, third, inward and outward gas flows are induced from zones of minima toward zones of maxima of perturbed specific mass, leading eventually to the possible formation of gaseous annular structures in the disc. The results presented may be applied in various astrophysical contexts to slowly rotating thin gaseous discs of negligible relative mass, submitted to small radial periodic perturbations.
