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arXiv · 2610.20546

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

Abstract

Parker Solar Probe (PSP) revealed the ubiquity of switchbacks (SBs), sharp, localised magnetic deflections in the nascent solar wind, renewing interest in their origin. One proposed mechanism involves solar jets: collimated, impulsive features driven by magnetic reconnection that launch Alfvénic torsional wavefronts into the heliosphere. We test whether realistic spacecraft sampling of a propagating solar jet produces in-situ signatures consistent with PSP observations. We also examine the 3D magnetic topology of the resulting structures and how deflection amplitudes evolve with the ambient plasma environment. We perform a 3D magnetohydrodynamic simulation of a solar jet in the ambient solar wind, embedding a virtual spacecraft trajectory based on PSP's actual 22nd-perihelion orbit to generate synthetic measurements. The simulation reproduces SB-like signatures with durations and profiles consistent with PSP observations, confirming earlier results from simplified trajectories. We visualise the fully 3D magnetic topology of a jet-driven SB region, identifying two field-line families: one with a single deflection and another with two sequential deflections along the same field line. Both are outward-propagating Alfvénic structures. Deflection amplitudes depend strongly on background plasma $β$, increasing substantially in low-$β$ regions and evolving more moderately where $β\sim 1$. These results show that solar jets can produce Alfvénic, SB-like structures along realistic spacecraft trajectories. Their topology is inherently 3D and structurally diverse, and their evolution depends on ambient plasma $β$. Complete magnetic reversals would require longer residence times in low-$β$ environments. Our findings support a solar origin for a fraction of SBs and constrain interpretations of their underlying magnetic structure.

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Jade Touresse, Etienne Pariat, Clara Froment, Peter F. Wyper. 2026-10-14. Dynamics of a switchback-like magnetic deflection induced by a propagating coronal jet. https://doi.org/10.1051/0004-6361%2F202659513

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