Historical review of electron beam ion sources (invited)

Thirty years have passed since the modern concept of the production of highly charged ions in dense electron beams was first proposed, and less since the first electron beam ion source (EBIS) was built and tested. Milestones from the EBIS history, and future prospects are described in view of today's needs in the production and use of highly charged ions. Various versions of EBIS, such as the classic EBIS, the electron beam ion trap-EBIT, the cross-over EBIS (T)-XEBIS/T and others were constructed, studied, and used in different laboratories. The ion-by-ion and "evaporative'' cooling techniques are used to increase the time of ion confinement in an electron beam, ion charge states and ion yield. An alternative way to increase the ion yield is an increase of the electron beam current. The different concept of an ion source based on EBIS which uses multiple reflection of primary electrons and formation of a so-called electron string state is studied as well. Stability of electron-ion systems and nonexcitation of internal EBIS structure are the main goals in the present EBIS studies. Fast extraction of ions from EBIS, which can be done during several microseconds makes efficient the single turn injection into ion synchrotrons. (C) 1998 American Institute of Physics.