Cube polywell, electric field, part VI

In our last experiments we placed the electron guns at polywell coil faces and analyzed the fields. Here lets put them at the corners of the cube.

Lets use the same old parameters: radius R=0.15m, coil thickness 0.07m, coil spacing 0.01m. Lets simulate the electron guns as small spheres placed at all 8 corners.

Lets put a sphere of uniform charge in the middle of the system and see how the fields shape up:

The electric potential

The electric field magnitude

The electric field with logarithmic magnitude

The electric field lines

The electric charge distribution (red means more positive charge, blue more negative charge, green less positive/negative charge)

Lets see how the potential well and electron acceleration from the electron gun towards the system relate to the space charge in the middle.

Compared to the electron gun placement at faces the acceleration is greater and the acceleration is flatter in response to the accumulating space charge. Also in previous electron path simulations it appears that the electrons are not as inclined to climb up the corner cusps as well as face cusps. Based on this one could say placing the e-guns at corners makes more sense than placing them at faces.

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