ON EMITTANCE GROWTH OF STRONGLY COUPLED HEAVY-ION BEAMS

In intense, strongly coupled heavy ion beams collisions between beam particles become important. We investigate their influence on the beam's phase-space dimensions in terms of averaged quantities. A model is developed where the emittance increases due to a temperature anisotropy driven by the envelope oscillations caused by a periodic focusing structure. A set of coupled differential equations is derived which extend the envelope equations by including the dynamics of the emittances. From these equations, estimates for the average emittance growth rates can be made. The predictions of the model are tested by comparison with numerical results obtained from molecular dynamics simulations.