Studies of an Unneutral Electron Cloud in the CFIA
In the Collective Focusing Ion Accelerator (CFIA) scheme, a non-neutral electron cloud is trapped in a multiple mirror toroidal magnetic field. The electrons' radial electrostatic field serves to confine and focus an accelerated ion beam. The ion beam, with a density up to 10% that of the electrons', is accelerated by an induced toroidal electric field. The induced toroidal electric field, however, is not strong enough to overcome the mirror force acting on the electrons. This scheme enables the construction of a very small radius accelerator in the GeV range. As a first stage in the development of the CFIA, it is necessary to demonstrate trapping and stability of a non-neutral electron cloud over a long time (a few msec). It is also necessary to show that the electron cloud remains confined to the mirror cells when an accelerating toroidal electric field is applied. 5 refs.