gas { A beam enters the system and causes ionization. the pressure is 1 millitorr } Region { Grid { J = 10 x1s = 0.0 x1f = 0.1 n1 = 1.0 K = 10 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 = 5.0E-10 ElectrostaticFlag = 1 Rule { Limit dt <= 0.0 Fatal -- time step must be positive } } MCC { gas = Ar pressure = .001 eSpecies = electrons iSpecies = argon } Species { name = electrons m = 9.11E-31 q = -1.6e-19 collisionModel = 1 } Species { name = argon m = 6.68e-28 q = 1.6e-19 subcycle = 10 } Species { name = secelectrons m = 9.11E-31 q = -1.6e-19 } BeamEmitter { speciesName = electrons j1 = 0 k1 = 0 j2 = 0 k2 = 5 normal = 1 np2c = 10000 I = -0.001 thetadot = 0.0 v1drift = 3.0e6 Secondary { secondary = 0.5 secSpecies = secelectrons iSpecies = argon } } Conductor { j1 = 0 k1 = 5 j2 = 0 k2 = 10 normal = 1 } Conductor { j1 = 0 k1 = 10 j2 = 10 k2 = 10 normal = -1 } Conductor { j1 = 10 k1 = 10 j2 = 10 k2 = 0 normal = -1 } CylindricalAxis { j1 = 0 k1 = 0 j2 = 10 k2 = 0 normal = 1 } }