We shoot electrons from the center of the cube polywell at different b-field levels (different coil currents) and see how long they on average are confined within the system limits.
Coil radius is R=0.15m and spacing between coils is S=0.07 (as per the scheme). All electrons are shot at 5000eV.
Electrons are shot from the middle of the system randomly towards a face of the cube (face is rectangular and larger than the coil itself due to spacing). Exactly 5000 electrons are randomly shot for each b-field (current) level.
Coils are simulated by single current loops. No e-fields are present in the system. Collisions with coils are not accounted for.
An electron is considered to have left the system when it's more than 3*radius=0.45m from the middle of the system.
We add up all the times of the 5000 electrons, divide by 5000 to get an average and multiply by velocity to get the average path length.
Shooting 10 electrons from the center to the right face.
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