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

¹ Max-Planck-Institut für Sonnensystemforschung, 37077 Göttingen, Germany
² National Institute for Astrophysics (INAF), Institute for Space Astrophysics and Planetology (IAPS), Via Fosso del Cavaliere 100, 00133 Rome, Italy
³ Solar-Terrestrial Centre of Excellence, Solar Influences Data analysis Centre, Royal Observatory of Belgium, 1180 Brussels, Belgium
⁴ Skobeltsyn Institute of Nuclear Physics, Moscow State University, 119991 Moscow, Russia
⁵ Department of Physics, Imperial College London, SW7 2AZ London, UK
⁶ Mullard Space Science Laboratory, Holmbury St Mary RH5 6NT, UK
⁷ Physikalisch-Meteorologisches Observatorium Davos, World Radiation Center, 7260 Davos Dorf, Switzerland
⁸ Die Eidgenössische Technische Hochschule Zürich, 8093 Zürich, Switzerland
⁹ Institut für Sonnenphysik (KIS), Georges-Köhler-Allee 401a, 79110 Freiburg, Germany
¹⁰ Institut de Recherche en Astrophysique et Planétologie, CNRS, Université de Toulouse, CNES, Toulouse, France
¹¹ Southwest Research Institute, San Antonio, TX 78238, USA
¹² RAL Space, UKRI STFC Rutherford Appleton Laboratory, Didcot OX11 0QX, UK
¹³ Southwest Research Institute, Boulder, CO 80302, USA
¹⁴ Space Science Division, Naval Research Laboratory, Washington DC 20375, USA

^⋆ Corresponding author; chitta@mps.mpg.de

Received: 24 October 2024
Accepted: 25 November 2024

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.