Solar wind dynamical structures, jets and switchbacks: emergence and evolution – SOLSTICES

The Parker Solar Probe (PSP), launched in 2018, has unraveled a much more dynamic solar wind than expected by previous theories and observations. In particular, it has observed many magnetic field reversals, associated with velocity jets, during its perihelia. These so-called ‘switchbacks’, have been studied extensively since their discovery, but their origin remains unknown. They could be related to the two main theories of coronal heating and solar wind acceleration. They are indeed fully part of the solar wind turbulence spectra. Turbulence creates dissipation at small scales and is believed to be the main source of energy for the expanding solar wind. Interestingly, PSP data has also revealed characteristic scales close to the Sun’s surface motions, which suggests that switchbacks' origin could be related to reconnection in the low corona. This eruptive events are the main alternative theory to turbulence, to explain coronal heating. This project aims at studying the emergence and evolution of these structures, using numerical simulations and observations from PSP and the European solar mission Solar Orbiter. We will model the reconnection process in the low corona and study, through MHD simulations, the propagation of these structures in realistic solar wind solutions. We will use in-situ and remote sensing observations to study the sources of the switchbacks and their properties. The project relies on the numerical expertise of the PI and on the ideal position of IRAP on both missions, which is heavily involved in several instruments: co-I PSP/SWEAP and PSP/WISPR, PI of SO/PAS, co-I of SO/MAG and SO/HIS. The project plans at hiring one PhD student for 3 years and one postdoc for 2 years.