发表机构
University of Delaware; Smithsonian Astrophysical Observatory–Harvard & Smithsonian（特拉华大学; 史密森天体物理台-哈佛与史密森学会）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
帕克太阳探测器在亚阿尔文日冕中首次观测到极区冕洞状快速太阳风，发现其湍流已充分发展且高度不平衡，为太阳风湍流演化提供新约束。
AI 中文摘要
帕克太阳探测器在2025年3月第23次近日点附近，采样了一段延伸的亚阿尔文太阳风区间，该区间可能源自一个大型赤道冕洞。在距日心约10个太阳半径处，该区间风速大多高于400 km/s，是亚阿尔文太阳日冕中观测到的首个“极区冕洞状（PCH-l）快速”太阳风实例。我们利用帕克太阳探测器的测量数据，表征了这一独特区间的湍流特性。尽管采样点位于名义阿尔文表面内部深处，湍流似乎已充分发展，同时保持强横向性和高度不平衡性，表现出较大的交叉螺旋度。这些观测为理解太阳风湍流在下日冕中的发展与演化提供了新的约束条件。
英文摘要
Parker Solar Probe, near its 23rd perihelion in March 2025, sampled an extended interval of sub-Alfvénic solar wind likely originating from a large equatorial coronal hole. At heliocentric distances of approximately 10 solar radii, with speed mostly above 400 km/s, this interval is a first example of ``polar coronal hole-like (PCH-l) fast" solar wind observed in the sub-Alfvénic solar corona. We characterize the turbulence properties of this unique interval using Parker Solar Probe measurements. Despite being sampled well inside the nominal Alfvén surface, the turbulence appears to be already well developed while remaining strongly transverse and highly imbalanced, exhibiting a large cross helicity. These observations provide new constraints on the development and evolution of solar wind turbulence within the lower corona.
CommentsAccepted for publication in The Astrophysical Journal Letters
