发表机构
National Institute of Science Education and Research; Homi Bhabha National Institute; University of Rochester; Center for Integrated Research Computing, University of Rochester; National Technical Institute for the Deaf, Rochester Institute of Technology; Center for Computational Relativity and Gravitation, Rochester Institute of Technology（印度科学教育与研究国家研究所; 霍米·巴巴国家研究所; 罗切斯特大学; 罗切斯特大学综合计算研究中心; 纽约理工学院聋人国家技术学院; 纽约理工学院计算相对论与引力中心）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
研究中子星喷流在共包层演化中的作用，采用三维全球流体动力学模拟，发现喷流能使更多包层质量解束缚，但有负反馈效应，阻止其主导解束缚过程及决定共包层演化结果。
AI 中文摘要
共包层（CE）阶段是双星演化中的关键阶段，目前仍不太清楚。对于中子星（NS）伴星，吸积可能远超爱丁顿极限，导致强大的双极喷流主导外流。本文利用三维全球流体动力学模拟，研究NS喷流在涉及红巨星分支恒星的CE事件中的作用。喷流最终穿透并突破包层，产生显著的低密度双极叶。与无NS喷流的模拟相比，喷流使约两倍的包层质量解束缚，但随着喷流突破并与包层能量解耦，解束缚率降低。喷流活动还使双星上的阻力略有减小。因此，强大喷流虽起重要作用，但负反馈效应阻止其主导包层解束缚和决定CE结果。
英文摘要
The common envelope (CE) phase is a key stage in binary star evolution that is still not very well understood. Once engulfed by the giant star, the binary companion may accrete envelope material. For neutron star (NS) companions, such accretion may in principle occur at mass rates several orders of magnitude above the Eddington limit and may result in outflows dominated by powerful bi-polar jets with mass-loss rates similar to the accretion rates. Such jets would impact the morphology of the system and the rate of envelope unbinding, which affect the duration and outcome of the CE event. Employing 3D global hydrodynamic simulations, we study the role of such NS jets in a CE event involving a red giant branch star. The jets eventually drill through and break out of the envelope, producing prominent low-density bi-polar lobes. The jets cause about twice as much envelope mass to be unbound ($\sim20\%$ of the envelope) as compared to simulations of the same duration without NS jets ($\sim10\%$). However, the rate of mass unbinding due to the jets decreases towards the ends of the simulations as the jets break out and energetically decouple from the envelope. Moreover, jet activity leads to slightly reduced drag on the binary, decreasing the rate of orbital energy transfer to the envelope. Hence, while such powerful jets can play an important role, negative feedback effects tend to prevent them from dominating envelope unbinding and dictating CE outcomes.
Comments13 pages, 9 figures, 1 table, ApJ, in press
