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arXiv · 2411.16513

Coronal hole picoflare jets are progenitors of both fast and Alfvénic slow solar wind

L. P. Chitta·Z. Huang·R. D'Amicis·D. Calchetti·A. N. Zhukov·E. Kraaikamp·C. Verbeeck·R. Aznar Cuadrado·J. Hirzberger·D. Berghmans·T. S. Horbury·S. K. Solanki·C. J. Owen·L. Harra·H. Peter·U. Schühle·L. Teriaca·P. Louarn·S. Livi·A. S. Giunta·D. M. Hassler·Y. -M. Wang
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Abstract

Solar wind, classified by its bulk speed and the Alfvénic nature of its fluctuations, generates the heliosphere. The elusive physical processes responsible for the generation of the different types of this wind are a topic of active debate. Recent observations reveal intermittent jets, with kinetic energy in the picoflare range, emerging from dark areas of a polar coronal hole threaded by open magnetic field lines. These could substantially contribute to solar wind. However, their ubiquity and direct links to solar wind have not been established. Here, we report a unique set of remote-sensing and in situ observations from the Solar Orbiter spacecraft that establish a unified picture of fast and Alfvénic slow wind, connected to the similar widespread picoflare jet activity in two coronal holes. Radial expansion of coronal holes ultimately regulates the speed of the emerging wind.

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L. P. Chitta, Z. Huang, R. D'Amicis, D. Calchetti, A. N. Zhukov, E. Kraaikamp, C. Verbeeck, R. Aznar Cuadrado, J. Hirzberger, D. Berghmans, T. S. Horbury, S. K. Solanki, C. J. Owen, L. Harra, H. Peter, U. Schühle, L. Teriaca, P. Louarn, S. Livi, A. S. Giunta, D. M. Hassler, Y. -M. Wang. 2025-11-06. Coronal hole picoflare jets are progenitors of both fast and Alfvénic slow solar wind. https://doi.org/10.1051/0004-6361%2F202452737

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