发表机构
Université Côte d'Azur; Université d'Orléans; Université de Toulouse; Université Lyon 1（蔚蓝海岸大学; 奥尔良大学; 图卢兹大学; 里昂第一大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本文发现吸积盘模拟中参考系选择会影响不稳定性分析结果，提出“括号模式”并指出边界依赖问题，强调解释不对称盘模拟需谨慎。
AI 中文摘要
如果吸积盘内的质量分布不对称，它将对中心天体施加引力。中心天体随后必须偏离参考系原点，导致对盘产生非典型的引力。本系列论文的目标是研究这种反馈回路的稳定性。在第一篇论文中，我们报告了一个令人惊讶的发现：参考系的选择会影响解析方程中所包含的波和不稳定性的数量及性质。为了说明这一点，我们使用一个简单的例子：Sanchez等人（2025，附录A.3）发现的模式。我们首次对这些模式进行了解析描述，解释了它们的物理机制，并提议将其称为“括号模式”，因为它们源于分部积分中的括号一侧。我们表明，同一个盘在恒星中心参考系中可能是稳定的，但在质心参考系中却是不稳定的。这是因为模拟域的边界依赖于参考系。为避免这一问题，必须对整个盘进行建模，从中心腔一直延伸到外边缘。但这在计算上极其昂贵，而且有些盘根本没有中心腔。我们的结果表明，在解释不对称盘的模拟结果时需要极度谨慎，并且我们所在的领域可能尚未拥有对中心天体反射运动进行建模的工具。
英文摘要
If the mass distribution within an accretion disc is asymmetric, it will exert a gravitational pull on its central object. The central object must then move away from the origin of the reference frame, resulting in atypical gravitational pulls on the disc. The goal of the present series of papers is to investigate the stability of this feedback loop. In this first paper, we report a surprising finding: the choice of reference frame affects the number and nature of the waves and instabilities contained in the analytical equations. To show this, we use a simple example: the modes discovered by Sanchez et al. (2025, Appendix A.3). We provide the first analytical description of those modes, we explain their physical mechanism, and propose to call them 'bracket modes' because they arise from the bracket side of an integration by parts. We show that the same disc can be stable in the stellocentric reference frame but unstable in the barycentric reference frame. This is because the boundaries of the simulation domain are frame-dependent. To avoid this, one must model the entire disc all the way from the central cavity to the outer edge. But this is prohibitively expensive, and some discs do not have a central cavity anyway. Our results suggest that extreme caution is required when interpreting simulations of asymmetric discs, and that our community may not have the tools to model the reflex motion of the central object yet.
Comments10 pages, 5 figures
