That would be the job of the electric field accelerating the particles…..

And since the flux tubes are flows of charged particles, that constitutes a current flow.

Charged particles follow the magnetic field lines which would take them in and out of the torus.

Remember our own Van Allen belts, where AFAIK particles are confined from the poles by magnetic mirroring. (I.e. when the field lines converge they force gyrating particles to revert.)

I assume the post was short on details as the physics seems to be well established. The flux tube is a magnetic flux tube similar to the ones on the suns surface. This is what confines the electric current along the tube.

You should not assume that plasma currents necessarily is due to individual ions, and consequently that the density of a plasma must reflect the density of a current through parts of it. In fact, I note that these particular currents are known to have particles typically coupled by way of fields I wouldn’t know that, because I haven’t studied these specific phenomena. But it is a recurring phenomena.

“and these travel along the magnetic field lines, slamming into Jupiter’s atmosphere.”

First of all, I misspoke. I said sodium ion when I meant to say sulfur ion. Now if you consider the two paragraphs above you can see that they are contradictions. If the ions are confined to the torus far away from Jupiter then they obviously cannot slam into the Jovian atmosphere in the polar regions. It’s got to be one or the other. The magnetic field lines do not run parallel to the green torus in the picture but rather perpendicular to it (roughly north-south but arcing around to connect with both the Jovian north magnetic pole and the Jovian south magnetic pole). Charged particles follow the magnetic field lines which would take them in and out of the torus.

The torus might well be made up of neutral sulfur atoms expelled from Io which have not yet been ionized. They would tend to follow the same orbit as Io and would essentially be tiny moons of Jupiter following along the same orbit. Once they become ionized they follow the magnetic field lines which take them out of the torus. But of course, this was never explained in the initial post although it’s a reasonable conclusion. And the initial post had the erroneous statement that Jupiter’s magnetic field directly caused the ionization to begin with.

I would like to answer to one or two questions raised in the comments.
-First of all, volcanism at Io is pretty well explained by the effect of tidal forces without the need of any electric current. That fact is that Io is very close to a giant planet and that it orbits quasi-exactly twice faster than Europa and four times faster that Ganymede. This resonance perturbs Io’s orbit and huge tidal forces distort Io, which generates heat and thus volcanism.

-What ionizes the SO2 neutral gas is both UV radiation (from the sun) and electron impact.

-The confinement of the torus particles is an observational fact (Earth observatories and various probes passing by pictured and measured it). Ions are frozen on their field line and can only spiral along it. Since they rotate around Jupiter as fast as the magnetic field (10h instead of 42h for Io), they experience strong centrifugal forces that confine them as far as possible from Jupiter, i.e. in the plasma torus.

Thus, physical sputtering with electron sucks.

“electro machine” material off the surface

That is bona fide sputtering, and is analogous to solar wind sputtering of atmospheres.

But the volcanoes on Io is volcanoes.

Btw, the sputter rate of electron beams is ridiculously low, as electrons have 1/2000th of hydrogen mass. Instead they vaporize material due to induced heat.

Huh? I’d like the mechanism for this explained a little bit better. Isn’t it a whole lot more probable that the protons and electrons buzzing around in Jupiter’s magnetic field slam into these sodium atoms and knock electrons off of them. How could the magnetic field directly ionize the sodium atoms?

Also, the green torus of sodium ions in the image makes no sense to me. Once these sodium atoms are ionized they will spiral around Jupiter’s magnetic field lines and go back and forth between the north Jovian magnetic pole (or directly above it) and the south Jovian magnetic pole until they interact with the Jovian atmosphere and get absorbed. This is similar to how protons and electrons interract with earth’s magnetosphere to generate the aurora borealis. The main point is that the sodium ions will not be constrained to a toroidal region since there is nothing keeping them in that region of space. So the whole picture looks wrong to me.