标题： 高度 eccentric AGB-主序星双星的化学示踪剂 显示英文标题

标题： Chemical tracers of a highly eccentric AGB-main sequence star binary

摘要： 双星相互作用被提出用来解释围绕演化恒星（包括渐近巨星分支（AGB）星和行星状星云）观测到的各种盘状结构。解析AGB星周围的包层的研究已经揭示了螺旋结构、盘状结构和双极喷流，这些结构的形成归因于与伴星的相互作用。 我们首次使用化学与动力学联合分析方法，揭示了W Aql（一个包含AGB星和主序伴星的双星系统）的高度偏心且长周期的轨道。 我们的研究结果基于各向异性SiN发射、首次探测到的S型星周围的NS和SiC分子以及CO发射中的密度结构。 所有这些特征都被解释为在近日点相遇时形成的。 基于天体化学的方法可以对包含AGB星的长周期双星系统的轨道参数提供严格的限制，并可应用于其他系统。 显示英文摘要

摘要： Binary interactions have been proposed to explain a variety of circumstellar structures seen around evolved stars, including asymptotic giant branch (AGB) stars and planetary nebulae. Studies resolving the circumstellar envelopes of AGB stars have revealed spirals, discs and bipolar outflows, with shaping attributed to interactions with a companion. For the first time, we have used a combined chemical and dynamical analysis to reveal a highly eccentric and long-period orbit for W Aquilae, a binary system containing an AGB star and a main sequence companion. Our results are based on anisotropic SiN emission, the first detections of NS and SiC towards an S-type star, and density structures observed in the CO emission. These features are all interpreted as having formed during periastron interactions. Our astrochemistry-based method can yield stringent constraints on the orbital parameters of long-period binaries containing AGB stars, and will be applicable to other systems.