Work

Dynamics of a switchback-like magnetic deflection induced by a propagating coronal jet

Year: 2026

Type: article

Abstract: Context. The Parker Solar Probe (PSP) mission revealed the ubiquity of switchbacks (SBs), i.e. sharp and localised magnetic deflections, in the nascent solar wind. This finding has sparked significant interest in their origin and formation mechanisms. Among the proposed scenarios, a solar origin associated with solar jets has emerged. Solar jets are collimated, impulsive, and sharp-edged features associated with magnetic reconnection and they generate an Alfvénic torsional wavefront propagating into the heliosphere. Aims. In this study, we investigate whether a realistic spacecraft sampling of a propagating solar jet can produce synthetic in situ signatures consistent with PSP-observed SBs. We also characterise the three-dimensional (3D) magnetic topology of the underlying structure and assess how the magnitude of the magnetic deflection evolves with the surrounding environment. Methods. We performed a 3D magnetohydrodynamic simulation of a solar jet propagating into the ambient solar wind. A virtual spacecraft trajectory, constructed from the actual PSP orbit during its 22nd perihelion, was embedded within the simulation to generate synthetic in situ measurements. Results. The simulation reproduces SB-like magnetic signatures with durations and profiles consistent with PSP observations, confirming earlier results obtained using simplified trajectories. For the first time, we directly visualised the fully 3D magnetic topology of a jet-driven SB region. Two distinct families of magnetic field lines are identified: one exhibiting a single magnetic deflection, and another showing two sequential deflections propagating along the same field line. In both configurations, the deflections act as outward-propagating Alfvénic structures. The magnitude of the magnetic deflection is strongly modulated by the background plasma β , with significant amplification in low- β regions and a more moderate evolution where β ~ 1. Conclusions. These results demonstrate that propagating solar jets can naturally produce Alfvénic, SB-like structures when sampled along realistic in situ trajectories. The magnetic topology of SB regions is inherently 3D and structurally diverse. Their evolution depends on the surrounding plasma β , with complete magnetic reversals requiring longer residence times in low- β environments. This study supports the interpretation that at least a fraction of the SBs observed by PSP may have a solar origin and it provides new constraints for interpreting PSP measurements in terms of their underlying magnetic structure.

Source: Astronomy and Astrophysics

DOI: 10.1051/0004-6361/202659513

Authors: J. Touresse, E. Pariat, C. Froment, P. F. Wyper