Aston Labs

Changing step size from 10 ns to 5 ns causes a shift of about 2.4 Hz, but leaves relative peak separation nearly unaffected:

For related simulations, oscillation amplitude was found to be conserved to within 0.02% during 870 ms propagation time for 5 ns step size.

As another check, the potential was recalculated with truncation but without the gap between outer electrodes. Numerical values for the radial and axial electric fields were compared to those from the analytical expressions:

Numerical values of Er(r, z = 0) are within 0.5% and Ez(r = 7 mm, z) are within 0.2% of the analytical expressions.