Potential structure near a probe in a flowing magnetoplasma and current collection

Physics – Plasma Physics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

6

Space Plasma Physics: Charged Particle Motion And Acceleration, Space Plasma Physics: Kinetic And Mhd Theory, Space Plasma Physics: Numerical Simulation Studies, Space Plasma Physics: Spacecraft Sheaths, Wakes, Charging

Scientific paper

The distributions of plasma and potential near an electric probe in a relative motion with respect to a magnetized plasma are studied by means of three-dimensional (3-D) numerical simulations. The relative motion is simulated by a plasma flowing past the probe across the ambient magnetic field. The plasma flow is imposed by a convection electric field E_o. A probe with a positive potential bias is considered. The prominent features of the potential distribution include (1) wings of positive potential perturbations extending along the magnetic field and swept forward in the direction of the plasma flow and (2) a ``fan'' shaped structure in planes transverse to the magnetic field in the region where the convection electric field E_o is opposed by space charge electric fields. The wing-like structure can be interpreted in terms of electrostatic plasma waves belonging to the oblique resonance cone in a magnetized plasma. The relative flow causes the formation of a ``bow shock'' in front of the probe, where plasma density is enhanced due to the combined effect of the retardation of the flowing ions and the modification in the E_×B_ drift of the electrons in the sheath of a positive probe. The electron collection by the probe is significantly enhanced above the theoretical upper bound current obtained from the conservation of energy and the canonical angular momentum for the case without the relative motion. The current in the plasma, contributing to the collection of electrons by the probe, flows in a magnetic field-aligned channel in the vicinity of the probe where electric fields parallel to the magnetic field are relatively strong. Electron flux is fed into the channel all along its length by the E_×B_ drift in the self-consistent electric field, considerably enhancing the current collected by the probe. The field-aligned current channel is localized near the probe where parallel electric fields dominate; it does not extend to infinity along the probe's magnetic shadow, unlike that for the case of a nonflowing plasma.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Potential structure near a probe in a flowing magnetoplasma and current collection does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Potential structure near a probe in a flowing magnetoplasma and current collection, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Potential structure near a probe in a flowing magnetoplasma and current collection will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1808474

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.