Is the “tail” which is a negative tail actually sign of plasma propulsion using Magnetoplasmadynamic thruster technology?#
Magnetoplasmadynamic thruster Magnetoplasmadynamic thruster - Wikipedia
“Generally, a gaseous material is ionized and fed into an acceleration chamber, where the magnetic and electric fields are created using a power source. The particles are then propelled by the Lorentz force resulting from the interaction between the current flowing through the plasma and the magnetic field (which is either externally applied or induced by the current) out through the exhaust chamber.”
Alternatively might 3I/ATLAS be using "plasma- sail " propulsion based on plasma magnet technology? https://www.niac.usra.edu/files/studies/final_report/860Slough.pdf
A magnetoplasmadynamic (MPD) thruster (MPDT) is a form of electrically powered spacecraft propulsion which uses the Lorentz force (the force on a charged particle by an electromagnetic field) to generate thrust. It is sometimes referred to as a Lorentz Force Accelerator (LFA) or (mostly in Japan) MPD arcjet.
Or even a combination of the two technologies?