发表机构
São Paulo State University-UNESP; Observatório Nacional/MCTI（圣保罗州立大学; 国家天文台）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究以Máni为模型，通过多种方法分析带深赤道陨石坑的不规则天体周围粒子稳定性，发现自旋轨道共振结构及其对旋转速率和质量比的依赖，为碎片环形成提供新机制。
AI 中文摘要
受海王星外天体（TNO）Máni 的特殊特征以及半人马小行星和海王星外天体周围环系统的发现的启发，我们研究了围绕一个带有深赤道陨石坑的小型不规则天体周围粒子的稳定性。本研究是一个系列中的第三篇，该系列致力于非球对称天体周围的动力学。以 Máni 为参考模型（其陨石坑深度超过其半径的 10%），我们通过互补方法绘制了系统稳定性图：庞加莱截面（PSS）、生存图以及有限时间李雅普诺夫指数（FTLE）。在标称情形下，$1\\!:\\!1$、$2\\!:\\!1$、$3\\!:\\!1$ 和 $4\\!:\\!1$ 自旋轨道共振（SORs）被所有技术一致识别。显著的 $3\\!:\\!1$ SOR 在高偏心率下表现出分叉结构，与在 PSS 中较低雅可比常数下观察到的结构转变相匹配。增加旋转速率（$\lambda$）和陨石坑质量比（$\mu$）会加宽共振宽度并促进重叠，使 $2\\!:\\!1$ 和 $4\\!:\\!1$ SORs 逐渐占主导。较低的旋转速率允许稳定轨迹在高偏心率下持续存在，而 $1\\!:\\!1$ SOR 对较强扰动高度敏感，在最极端情况下消失。与质量异常模型（可清除 $2\\!:\\!1$ SOR 内部区域）相比，这里考虑的陨石坑配置在该附近保留了稳定区域，为不规则小天体周围碎片结构的形成和维持提供了替代情景。
英文摘要
Motivated by the peculiar features of the trans-Neptunian object (TNO) Máni and the discovery of ring systems around Centaurs and trans-Neptunian bodies, we investigate the stability of particles around a small irregular body hosting a deep equatorial crater. This study is the third contribution in a sequence devoted to the dynamics around non-spherically symmetric bodies. Using Máni as a reference model, whose crater depth exceeds 10% of its radius, we map the system stability through complementary methods: Poincaré surfaces of section (PSS), survival maps, and the finite-time Lyapunov exponent (FTLE). In the nominal case, the $1\!:\!1$, $2\!:\!1$, $3\!:\!1$, and $4\!:\!1$ spin-orbit resonances (SORs) are consistently identified by all techniques. The prominent $3\!:\!1$ SOR exhibits a bifurcated structure at high eccentricities, matching structural transitions observed at lower Jacobi constant values in the PSSs. Increasing the rotation rate ($λ$) and crater mass ratio ($μ$) enlarges resonance widths and promotes overlap, making the $2\!:\!1$ and $4\!:\!1$ SORs progressively dominant. Lower rotation rates allow stable trajectories to persist at higher eccentricities, whereas the $1\!:\!1$ SOR is highly sensitive to stronger perturbations and disappears in the most extreme cases. In contrast to mass-anomaly models, which can clear the region interior to the $2\!:\!1$ SOR, the crater configuration considered here preserves stable regions in this vicinity, suggesting alternative scenarios for the formation and maintenance of debris structures around irregular minor bodies.
