Naively, one would expect the current to be parallel to the magnetic field along a flux tube.

These sites of penetration are known as flux tubes.

At low temperatures the flux tubes are pinned in place and cannot move.

The Sun's magnetic field was intense, and its flux tubes, each a hundred yards across, became locked into the charged material.

The flux tubes can tangle, or break, but they can't intersect.

The flux tubes were blue in this coding, and they looked eerie.

This, Claire directed down onto the flux tubes around the hole.

The antimatter in their downwash cut straight through flux tubes.

Free of the flux tubes' grip, the wormhole itself accelerated away from the Sun.

Sunspots are also associated with larger flux tubes of 2500 km diameter.