Pickup processes: Related currents and magnetic fields from mass and momentum loading

Abstract:

Mass and momentum loading due to ionization and due to charge exchange between ions and neutrals within flowing, magnetized plasmas are generally referred to as “pickup”. Pickup plays an important role in the interaction of many planetary bodies with their surrounding plasmas, e.g., at the moons of Jupiter. Due to pickup the plasma flow can be strongly modified with associated strong magnetic fields perturbations. The magnetic field perturbations generated by pickup are frequently associated with so called “pickup currents”. In our presentation we will review physics and implications of the pickup process and discuss its related electric currents. Based on Vasyliūnas 2006 we will also critically assess a picture introduced by Goertz (1980) that the displacements of ions and electrons as a result of their acceleration and gyro-motions under the action of a motional electric field generates pickup currents directly responsible for the magnetic field and flow perturbations.