Zoom link :
https://cnrs.zoom.us/j/95003883304?pwd=MI0B5WLYiGZlzo3oAZUl5TAu4fta6q.1
Author :
Jade Touresse, 3rd-year Ph.D Student, at LPP
Abstract :
Parker Solar Probe (PSP) has recently detected localised magnetic
deflections in the nascent solar wind, known as switchbacks. These
intriguing phenomena, rarely observed near Earth, have captured the
interest of the scientific community because their origin remains uncertain.
One leading hypothesis suggests that the switchbacks may arise from solar
jets, dynamic plasma eruptions that occur frequently in the Sun’s lower
atmosphere.
To explore this scenario, I conducted 3D Magnetohydrodynamic
(MHD) parametric simulations of solar-jet-like events using the
Adaptatively Refined MHD Solver (ARMS) code. Based on the model of
Pariat et al. 2009 , the simulations explore how variations in the atmospheric
plasma β influence jet dynamics and propagation under different coronal
and solar wind conditions, including fully sub-Alfvénic regimes and varying
Alfvén surfaces.
The results reveal that U-loops, prevalent at jet onset, do
not propagate in the low-beta corona, preventing full magnetic reversals
from reaching the super-Alfvénic wind Touresse et al. 2024. Using a
simulated PSP trajectory through the magnetic wavefront of the jet, we
produced a 3D visualization of a switchback, along with synthetic in-situ
velocity and magnetic field data. Two distinct field-line configurations were
identified, whose evolution depends strongly on the surrounding plasma β.
Overall, these results demonstrate that jet-like events can generate and
propagate magnetic deflections, shedding light on the possible formation
processes of switchbacks.
