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Ion source development over the last 20 years at the IMP is reviewed. For versatile purposes, several types of ion sources have been involved in the research and development work at the IMP, i.e., the highly charged ECR (Electron Cyclotron Resonance) ion source, intense microwave ion source or the 2.45 GHz intense beam ECR ion source, and laser ion source (LIS). In the development of ECR ion sources, SECRAL (Superconducting ECR ion source with Advanced design in Lanzhou), Lanzhou ECR ion source, and Lanzhou all permanent magnet ECR ion source series have been made, which can cover the operation microwave frequency range of 10–28 GHz. The LIS with an Nd:YAG laser with a maximum output energy of 8 J in 8 ns pulse duration has been developed for very intense short pulse ion beams from solid materials such as C, Ti, Ni, Ag, and so on. Microwave ion sources have been built to produce intense pulsed or direct current beams from several mA to 100 mA for either high intensity accelerators or applications. This paper will give an overview of the high intensity ion source development at the IMP, especially on the recent progress and new results, such as the status of the fourth generation ECR ion source (first fourth generation ECR ion source), the production of recorded highly charged ion beams with SECRAL sources, key technology research studies, and so on. [ABSTRACT FROM AUTHOR]

Uranium ion beams were produced from electron cyclotron resonance (ECR) ion sources by sputtering method this year at the Institute of Modern Physics. At first, we chose the Lanzhou ECR No. 3 ion source to implement the production experiment of U ion beams. Finally, 11 e μA of U28+, 5 e μA of U32+, and 1.5 e μA of U35+ were obtained. A U26+ ion beam produced by the LECR2 ion source was accelerated successfully by the cyclotron. This means that the Heavy Ion Research Facility in Lanzhou (HIRFL) has accomplished the acceleration of the ion beam of the heaviest element according to the designed parameters. The Lanzhou ECR ion source No. 2 (LECR2), which was built in 1997, has served the HIRFL for eight years and needed to be upgraded to provide more intense high charge state ion beams for HIRFL cooling storage ring. We started the upgrading project of LECR2 last year, and the modified design just has been finished. [ABSTRACT FROM AUTHOR]

With a latest developed electric-sweep scanner system, we have done a lot of experiments for studying this scanner system and ion beam emittance of electron cyclotron resonance (ECR) ion source. The electric-sweep scanner system was installed on the beam line of Lanzhou electron resonance ion source No. 3 experimental platform of Institute of Modern Physics. The repetition experiments have proven that the system is a relatively dependable and reliable emittance scanner, and its experiment error is about 10%. We have studied the influences of the major parameters of ECR ion source on the extracted ion beam emittance. The typical results of the experiments and the conclusions are presented in this article. [ABSTRACT FROM AUTHOR]

Many experiments have been made to produce metallic ion beams since 1998 at IMP (Institute of Modern Physics). We have designed a small oven that can reach a temperature of more than 1300 °C using 110 W electric power. Typical ion beam currents of 70 eμA of Ca12+, 60 eμA of Mg8+, 25 eμA of Pb27+ have been provided to the IMP cyclotron operation by the LECR2 (LanZhou ECR No. 2). We have also obtained some good results by the metallic ions from volatile compounds method on LECR3 (LanZhou ECR No. 3). © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

In order to study the transmission properties of multicharged ion beams between the electron cyclotron resonance (ECR) ion source and the analyzing magnet, a new diagnostic system composed of three Wien filters with three single wires has been built and installed on the IMP ECR source test bench. The single wire is used to measure the beam profile and the beam density distribution, and the Wien filter is used to measure the charge state distribution of ion beam. The single wire and the Wien filter were tested successfully. With this diagnostic system, the beam profile, charge state distributions and beam losses along the transmission line from IMP LECR3 to the analyzing magnet are experimentally studied in different conditions of the ion source. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

We have designed and built an emittance scanner which was installed at the beam line of IMP LECR3. The scanner measures the emittance of ECR ion source by the method of electric-sweep, typically named as Electric-Sweep Scanner (ESS). The horizontal and vertical emittances were both measured by two ESSs at the beam line of IMP LECR3. Some preliminary results were obtained. The detailed results and discussions will be presented. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

We are developing a multicharged ion beam transport program. The program is dedicated to numerical simulation of the behavior of highly charged ion beam and optimization of beam optics in transport lines and is realized on a PC with Windows user interface of Microsoft Visual Basic. Among all the ions with different charge states in the beam, the exchange of electrons between highly charged ions and low charged ions or neutral atoms of residual gas are taken into account using classical molecular over-barrier model and Monte Carlo method. Therefore, the code is able to describe the changing charge state distribution along the transmission line. The initial charged state distribution of ions may be input from experimental data or calculated from some classical density distribution such as uniform, Gaussian, water bag, or parabolic. The main advantage of the code is the ability to simultaneously simulate a number of ions with different masses and charge states, particularly the decrease of the highly charge ions and the increase of low charged ions due to electron capture. Some simulation results for a transmission line of a highly charged ECR ion source are presented. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Electron cyclotron resonance (ECR) ion sources are used for cyclotron complex and atomic physics research at the Institute of Modem Physics (IMP). Intense beams of highly charged gaseous and metallic ions could be produced by the IMP 14.5 GHz ECR ion source (LECR2-Lanzhou Electron Cyclotron Resonance Ion Source No. 2). A particular emphasis has been put on the production of metallic ion beams recently. Metallic ion beams of Mg, Ca, Fe, Ni, Cu, Zn, and Pb were tested at the IMP 14.5 GHz ECR ion source (LECR2) to improve beam intensities and long-term stability. A new ECR ion source (Lanzhou Electron Cyclotron Resonance Ion Source No. 3), an upgraded version of the IMP 14.5 GHz ECR (LECR2) but with double-frequency wave heating (10 GHz+14.5 GHz), is under commissioning. The preliminary results of this new source will be presented. To satisfy the requirements of the heavy ion cooling storage ring that is under construction at IMP, a fully superconducting ECR ion source (Lanzhou Electron Cyclotron Resonance Ion Source with Superconducting Coils) with a completely new structure is being developed for the production of intense heavy ion beams of very high charge states, such as Xe[sup 30+] and U[sup 40+]. The superconducting magnet consists of three axial solenoid coils and six saddle-curved sextupole coils with a cold iron structure as field booster and clamp. At full excitation, this magnet assembly will produce maximum peak fields on axis of 4.0 T at the injection, 2.2 T at the extraction region, and a radial sextupole field of 2.0 T at plasma chamber wall. The design features and status of this new superconducting ECR ion source will be presented. [ABSTRACT FROM AUTHOR]

A new electron cyclotron resonance (ECR) ion source (LECR3—Lanzhou Electron Cyclotron Resonance Ion Source No. 3) has been constructed this year. The main purpose of this source is to provide highly charged ion beams for atomic physics and surface physics research. The design of this ion source is based on the IMP 14.5 GHz ECR ion source (LECR2—Lanzhou Electron Cyclotron Resonance Ion Source No. 2) with double rf heating by inserting waveguide directly and aluminum chamber. Furthermore, the volume of the plasma chamber is larger than that of LECR2 so as to increase the rf power and improve beam intensity for highly charged ions. But the hexapole field on the chamber wall is kept the same value in order to compare with the performance of LECR2. After only four days conditioning the first test results were obtained. The final result of this ion source is expected to be better than LECR2's. [ABSTRACT FROM AUTHOR]