Atomic Physics of Highly Ionized Atoms

The last decade has seen dramatic progress in the development of devices for producing mu1ticharged ions. Indeed it is now pos­ sible to produce any charge state of any ion right up through 92 fully-stripped uranium (U +). Equally dramatic progress has been achieved in the energy range of the available ions. As an example, fully-stripped neon ions have been produced in useable quantities with kinetic energies ranging from a few ev to more than 20 Gev. Interest in the atomic physics of multicharged ions has grown apace. In the fusion program, the spectra of these ions is an im­ portant diagnostic tool. Moreover the presence of mu1ticharged ions presents a serious energy loss mechanism in fusion devices. This fact has motivated a program to study the collision mech­ anisms involved. In another area, mu1ticharged ions are present in the solar corona and the interstellar medium and knowledge of their collision properties and spectra is essential to understand­ ing the astrophysics. Other possible applications are to x-ray lasers and heavy ion inertial fusion. On a more fundamental level, new possibilities for testing quantum electrodynamics with mu1ti­ charged ions have emerged.