A status report of the multipurpose superconducting electron cyclotron resonance ion source (invited)

Abstract

Intense heavy ion beam production with electron cyclotron resonance (ECR) ion sources is a common requirement for many of the accelerators under construction in Europe and elsewhere. An average increase of about one order of magnitude per decade in the performance of ECR ion sources was obtained up to now since the time of pioneering experiment of R. Geller at CEA, Grenoble, and this trend is not deemed to get the saturation at least in the next decade, according to the increased availability of powerful magnets and microwave generators. Electron density above 10(13) cm(-3) and very high current of multiply charged ions are expected with the use of 28 GHz microwave heating and of an adequate plasma trap, with a B-minimum shape, according to the high B mode concept [S. Gammino and G. Ciavola, Plasma Sources Sci. Technol. 5, 19 (1996)]. The MS-ECRIS ion source has been designed following this concept and its construction is underway at GSI, Darmstadt. The project is the result of the cooperation of nine European institutions with the partial funding of EU through the sixth Framework Programme. The contribution of different institutions has permitted to build in 2006-2007 each component at high level of expertise. The description of the major components will be given in the following with a view on the planning of the assembly and commissioning phase to be carried out in fall 2007. An outline of the experiments to be done with the MS-ECRIS source in the next two years will be presented.

Evaluation of charge breeding options for EURISOL

“…This change may entail a modification of the RF power injection system, in case its original configuration is axial. The most advanced ECR ion sources in the world are SECRAL [26], VENUS [27], MS-ECRIS [28], SuSI [29] and A-PHOENIX [30]. While the first ones are fully superconducting systems, the last is a hybrid system combining High Temperature Superconducting (HTS) coils and a permanent magnet hexapole.…”

Study of the asymmetric magnetic field confining the plasma in an experimental ECR set-up

“…make it general, we now consider the typical magnetostatic profile relative to the case in which a single monochromatic wave at the frequency of 28 GHz is used to supply the source [3,[13][14][15][16]. Typical magnetic field profile on the z axis, relative to the case in which an electromagnetic wave at the frequency of 28 GHz is applied to a high-performance ion source.…”

“…Typical magnetic field profile on the z axis, relative to the case in which an electromagnetic wave at the frequency of 28 GHz is applied to a high-performance ion source. Then, by taking into account the power values commonly required to feed the cavity in the considered case, suitable dimensions for it can be chosen as length L C = 0.6 m and radius a C = 0.08 m [3,[13][14][15][16]. Practical rules for the ion source operation [1][2][3] require that there be a plasma chamber large enough to obtain a suitable and not-too-high average power density within it.…”

“…Practical rules for the ion source operation [1][2][3] require that there be a plasma chamber large enough to obtain a suitable and not-too-high average power density within it. Then, by taking into account the power values commonly required to feed the cavity in the considered case, suitable dimensions for it can be chosen as length L C = 0.6 m and radius a C = 0.08 m [3,[13][14][15][16].…”

“…A curve of the field along the z axis, obtained from (2.3) for the typical case considered here, is shown in Fig. 3 [3,[13][14][15][16]. The resulting values for the solenoid parameters, employed to achieve it, are listed in Table 1.…”