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Great efforts have been made to develop highly charged ECR ion sources for application of heavy ion accelerator and atomic physics research at IMP in the past few years. The latest development of ECR ion sources at IMP is briefly reviewed. Intense beams with high and intermediate charge states have been produced from IMP LECR3 by optimization of the ion source conditions including rf frequency extended up to 18GHz. 1.1 emA of Ar8+ and 325 eμ A of Ar11+ were produced. Dependence of beam emittance on those key parameters of ECR ion source, beam extraction and space charge compensation were experimentally studied at LECR3. Furthermore, an advanced superconducting ECR ion source named SECRAL is being constructed. SECRAL is designed to operate at rf frequency 18–28GHz with axial mirror magnetic fields 3.6–4.0 Tesla at injection, 2.2 Tesla at extraction and sextupole field 2.0 Tesla at the wall. The superconducting magnet with sextupole and three solenoids was tested in a test-cryostat and 95% of designed fields were reached. Construction status and planed schedule of SECRAL are presented. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

With the development of Electron Cyclotron Resonance Ion Source (ECRIS), very high performance ECRIS nowadays have been set up one by one around the world, such as the GTS in Grenoble, SERSE in Catania, LECR3 in Lanzhou and etc, which can produce very intense Multiply Charged Ion (MCI) beam. But till now, the study of the extracted MCI beam from an ECRIS remains open. In this article, we present a theoretical and experimental study of the extracted MCI beam. In the theoretical part, the influences of the extraction system on the extracted ion beam quality are mainly analyzed. The aspects that have influences on the extracted ion beam quality have been analyzed. With the instruction of the analysis, the PBGUNS code is used to simulate the influences of some important aspects concerning the extraction system. The influences of the extraction system geometry design, magnetic field, and the space charge effect will be detailedly presented in this article. In the experimental part, with an Electric-Sweep Scanner (ESS) emittance detection system, the influences on the extracted ion beam emittance of some typical parameters of ECRIS have been researched, such as the injected RF power, the RF frequency, the magnetic field and etc. The obtained results and the corresponding explanations are presented. Some of the results are well in accord with some empirical laws, but some other results seem to be disputed. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

Two new space charge compensation methods developed in IMP are discussed in this paper. There are negative high voltage electrode method (NHVEM) and electronegative charge gas method (EGM). Some valuable experimental data have been achieved, especially using electronegative gas method in O6+ and O7+ dramatic and stable increasing of ion current was observed. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

The stripping mode for production of multi-charged radioactive ion beams is discussed, and its advantages are also discussed. A 2.45 GHz ECRIS serving as the primary ion source was designed for production of singly charged radioactive ion beams. This source is compact, reliable, and economical. The magnetic field of the source provided by two permanent magnet rings has been calculated with POISSON code. Additionally, the structure of the source is presented. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

A high performance all permanent Electron Cyclotron Resonance Ion Source (ECRIS) LAPECR2 (Lanzhou All Permanent ECR ion source No. 2) has been under construction in IMP for one year. This ECRIS is running at 14.5GHz. The magnetic field configuration is designed according to the famous magnetic scaling laws: Binj = 1.4T (2.2T with an iron plug at the injection side), Bex1 = 1.1T, Bmin = 0.43T and Brad = 1.2T. According to the final design, the source body is φ650mm×560mm in dimension and about 900kg in weight. The source turns out to be the largest all permanent ECRIS in the world. To fabricate such an ion source is really very difficult, however we have succeeded in overcoming the many difficulties and the source has been set up recently. In this article, the typical parameters of the constructed ion source are presented. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]