Nonadiabaticity and high energy particle orbits in EBT

The scaling of hot electron ring temperatures in ELMO Bumpy Torus (EBT) and mirror experiments and results of recent ICH experiments on EBT-S suggest the scaling law rho/L approx. = 0.05, where rho is the gyroradius and L is the magnetic scale length. This is roughly the value at which conservation of the adiabatic invariant μ begins to break down. The behavior of μ(tau) and particle drift orbits are obtained by numerical integration of the equations of motion. In the absence of electric fields it is shown that nonconservation of μ for rho/L approx. = 0.05 is so weak that it has little effect on drift orbits and affects particle losses only through enhanced pitch scattering. Only for particle energies of about five times the temperature do rapid direct losses, due to magnetic moment jumps, start to become important