320kV ECR Platform
A 320kV ECR platform is now under construction in IMP. This ECR platform is supposed to deliver intense high charge state ion beams and medium charge state ion beams for atomic physics, material surface research and biology research.
· 2×Atomic, Molecular and Cluster
· 1.5×irradiative material +0.5×nuclear astrophysics
· 1×irradiative biology
A high performance ECRIS is meant to be put on this platform. Considering the virtues like simplicity, easy handling, electricity-free (except for the power supply for microwave generator), no need for high pressure cooling water, low running expense and long time running stability, an all permanent ECRIS LAPECR2 was then determined as the choice. The source LAPECR2 should be able to deliver tens of to hundreds of eµA medium charge state ion beams such as C4+, O6+, Ar8+, Xe20+ and at least several eµA high charge state ion beams such as Ar14+, Xe27+ and etc.
LAPECR2 has been successfully installed and has been mounted on the 320kV ECR platform. All the components are working properly now. The source has passed the 40kV HV insulation test without the ion beam extraction electrodes. With a stainless steel puller installed, the source can work without discharge at 25kV. The LAPECR2 source is believed to be the biggest all permanent ECR ion source in the world. It has the strongest magnetic field (without any iron plug), largest outer dimension and the heaviest weight. We have successfully assembled the magnetic body of the ion source at the middle of August 2004. The outer dimension of the source is measured to be Ø650mm×560mm. The weight of the magnetic body is about 900kg, and the source weight is expected to be more than 1 ton. According to the series of measurements, the magnetic field values are close to our original design, According to the comparison of the typical parameters of LAPECR2 and LECR2, some good results are expected.
Comparison of the typical parameters of LAPECR2 and LECR2
* with an iron plug at the injection side
The interactions between highly charged ions and materials (atoms, molecules, clusters, surfaces, and bio-molecules, etc) have great importance not only for fundamental interests but also for application researches . For not high energy collisions, the highly charged projectiles usually are provided by ECRIS or EBIT/S. The projectile energy is around 20q keV (where q is the projectile charge) and below, while for energies up to several 100q keV there is few facility available for experimental studies. In order to extend to higher impact energies, a project is presently being undergoing at the institute which aims to accelerate the ions up to 300q kV. The dynamical range of the projectile velocity will be from 0.3 a.u. to 2 a.u. covering electron capture dominant channel to ionisation dominant channel.
The permanent magnet ECR ion source sits on the high voltage platform, the ions are produced and extracted from the source. After charge state analysis, the ions are accelerated and leave the high-voltage platform. The following beam lines are equipped with five experimental terminals: for (1) surface studies, (2) atomic physics research (collision dynamics as well as spectroscopy with atomic or molecular target beams), (3) multi-purpose experimental terminal, the design is flexible and allows the external users to bring their own set-ups for experiments, (4) material science, and (5) biophysics searches, respectively.