default { Free expansion of the beam, with no applied magnetic field } Region { Grid { Geometry = 0 J = 5 x1s = 0.0 x1f = 0.1 n1 = 1.0 K = 5 x2s = 0.0 x2f = 0.02 n2 = 1.0 Rule { Limit n1 < 0.25 Fatal -- n1 < 0.25 grid spacing too nonuniform to ensure accuracy } Rule { Algebra J * K > 10000 Warning -- J*K >= 10000 may mean memory problems! } } Control { dt = 1.0E-11 Rule { Limit dt <= 0.0 Fatal -- time step must be positive } } Species { name = electrons m = 9.11E-31 q = -1.6e-19 } BeamEmitter { speciesName = electrons j1 = 0 k1 = 0 j2 = 0 k2 = 2 normal = 1 np2c = 1000000 I = 1 thetadot = 0.0 v1drift = 5e7 v2drift = 0 v3drift = 0 v1thermal = 0 v2thermal = 0 v3thermal = 0 } Conductor { j1 = 0 k1 = 2 j2 = 0 k2 = 5 normal = 1 } Conductor { j1 = 0 k1 = 5 j2 = 5 k2 = 5 normal = -1 } Conductor { j1 = 5 k1 = 5 j2 = 5 k2 = 0 normal = -1 } CylindricalAxis { j1 = 0 k1 = 0 j2 = 5 k2 = 0 normal = 1 } }