发表机构
Universitat de València; Observatori Astronòmic, Universitat de València; Institut de Ciències del Cosmos (ICC), Universitat de Barcelona（瓦伦西亚大学; 瓦伦西亚大学天文台; 巴塞罗那大学宇宙科学研究所）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究通过相对论流体动力学数值实验，证实恒星与Fanaroff-Riley I型射电星系喷流边界相互作用，可作为星际气体夹带的触发源，显著贡献喷流质量加载与减速。
AI 中文摘要
低功率河外喷流已知会在宿主星系内减速并释放大量能量，但其具体发生过程仍未明确。本研究旨在探究恒星作为Fanaroff-Riley I型射电星系中喷流质量加载、减速与耗散触发源的作用，该研究的动机源于一个理论模型，该模型提出与喷流边界相互作用的恒星可促进星际介质（ISM）气体被夹带进入喷流，利于混合与耗散。我们使用相对论流体动力学代码开展了恒星进入相对论流的数值实验，为在有限可控环境中评估结果，实验设置限定为三颗恒星与喷流边界的相互作用，尽管该恒星数量在大质量星系的内部千秒差距区域中可能是合理的。我们的结果可估算恒星进入喷流时被夹带的ISM气体量，结果显示演化恒星在数十秒差距、数千年的尺度上临时诱导的夹带量，与初始喷流质量率相当。这种夹带的发生方式是在恒星天体后方形成低压区，将周围气体拖入喷流流场。我们的结果证实，与喷流边界相互作用并作为ISM/剪切气体夹带催化剂的恒星，可对喷流质量加载与减速产生显著贡献。
英文摘要
Low-power extragalactic jets are known to be decelerated and dissipate large amounts of energy within their host galaxies. However, the exact process by which this occurs is still elusive. The aim of this work is to probe the role of stars as triggers of jet mass-loading, deceleration and dissipation in Fanaroff-Riley type I radio galaxies. This is motivated by a theoretical model that proposes that stars interacting with the jet boundaries could facilitate entrainment of interstellar medium (ISM) gas into jets, favouring mixing and dissipation. We have performed a numerical experiment of stars entering a relativistic flow, using a relativistic hydrodynamics code. Our setup is limited to the interaction of three stars with the jet boundary, in order to assess the results in a limited, controlled, environment, although this number of stars may be plausible in the inner kpc-region of a massive galaxy. Our results allow us to estimate the amount of entrained ISM gas as the stars enter the jet. We show that the entrainment temporally induced on scales of tens of parsecs and thousands of years by evolved stars is comparable to the initial jet mass rate. The way in which this entrainment happens is by the creation of a low pressure region behind the stellar objects, which drags ambient gas into the jet flow. Our results confirm that stars interacting with the jet boundaries, and acting as catalysts of ISM/shear gas entrainment, can significantly contribute to jet mass-load and deceleration.
