I stars have been bombarded with many meteorites which provided the heavy elements. I stars have been treated by an alien spaceship with an any-ion beam. Refer to the drawing below. Close to the sun, interstellar gas atoms loose one of their electrons and become ions. Interstellar ions are picked up with exactly the solar wind velocity.
Interstellar ions can reach up to twice the solar wind velocity after they are picked up.
Interstellar ions will only move along the magnetic field with their original velocity. Interstellar ions won't move at all, because they are not influenced by the solar wind and the magnetic field.