Related Experiment Video
Updated: Jul 11, 2026

Building Langmuir Probes and Emissive Probes for Plasma Potential Measurements in Low Pressure, Low Temperature Plasmas
Published on: May 25, 2021
Theory of weak bipolar fields and electron holes with applications to space plasmas
Martin V Goldman1, David L Newman, André Mangeney
1Department of Physics and CIPS, University of Colorado, Boulder, CO 80309, USA.
Abstract:
A theoretical model of weak electron phase-space holes is used to interpret bipolar field structures observed in space. In the limit ephi(max)/Te << 1 the potential of the structure has the unique form, phi(x) = phi(max)sech4(x/alpha), where phi(max) depends on the derivative of the trapped distribution at the separatrix, while alpha depends only on a screening integral over the untrapped distribution. Idealized trapped and passing electron distributions are inferred from the speed, amplitude, and shape of satellite waveform measurements of weak bipolar field structures.
Related Concept Videos
Theory of Strong Electrolytes
The Hall Effect
Electric Field of Parallel Conducting Plates
Consider a cross-section of a thin, infinite conducting plate having a positive charge. For such a large thin plate, as the thickness of the plate tends to zero, the positive charges lie on the plate's two large faces. Without an external electric field, the...
Electric Field of Two Equal and Opposite Charges
A separation of the positive and negative charges can lead to a weak, remnant effect of the positive and negative charges. The expectation is that the more the distance between the positive and...
The Electrical Double Layer
Potential Due to a Polarized Object
