标题： 由JWST揭示的碰撞星风双星Apep中的尘埃形成和演化 显示英文标题

标题： The formation and evolution of dust in the colliding-wind binary Apep revealed by JWST

摘要： 富含碳的沃尔夫-拉叶（WR）星是银河环境中碳质尘埃的重要贡献者，然而这些恒星周围尘埃的形成和后续演化机制和条件仍然是开放性问题。 在这里，我们展示了对WR+WR碰撞风双星Apep的JWST观测结果，揭示了由丰富细节子结构组成的复杂嵌套同心尘埃壳层。 这些壳层之间子结构的显著规律性表明，存在一个精确重复的形成机制，并且具有高度稳定的流出，即使在进入星际介质0.6 pc（假设距离为2.4 kpc）后仍保持一致的形态。 同心尘埃壳层显示出与球形流出略有偏差，这可能反映了沿偏心双星轨道的轨道调制，或恒星风的轻微非球形性。 追踪多层结构中尘埃的演化，我们测量了尘埃温度的变化，这种变化可以用非晶态碳成分在辐射热平衡中进行广泛描述。 温度分布和轨道周期提出了新的距离约束，支持Apep比之前估计的距离更远，从而减少了之前认为该系统特有的视线方向和天球平面风速差异。 显示英文摘要

摘要： Carbon-rich Wolf-Rayet (WR) stars are significant contributors of carbonaceous dust to the galactic environment, however the mechanisms and conditions for formation and subsequent evolution of dust around these stars remain open questions. Here we present JWST observations of the WR+WR colliding-wind binary Apep which reveal an intricate series of nested concentric dust shells that are abundant in detailed substructure. The striking regularity in these substructures between successive shells suggests an exactly repeating formation mechanism combined with a highly stable outflow that maintains a consistent morphology even after reaching 0.6 pc (assuming a distance of 2.4 kpc) into the interstellar medium. The concentric dust shells show subtle deviations from spherical outflow, which could reflect orbital modulation along the eccentric binary orbit or some mild degree of non-sphericity in the stellar wind. Tracking the evolution of dust across the multi-tiered structure, we measure the dust temperature evolution that can broadly be described with an amorphous carbon composition in radiative thermal equilibrium with the central stars. The temperature profile and orbital period place new distance constraints that support Apep being at a greater distance than previously estimated, reducing the line-of-sight and sky-plane wind speed discrepancy previously thought to characterise the system.