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This study compares experimental observations on the two challenges of Ion Cyclotron Resonance Heating (ICRH), namely the coupling of waves to the plasma and the enhanced impurity sputtering in EAST and WEST medium size tokamaks. In WEST, Lower Hybrid (LH) power helps improving ICRH coupling. In both machines experiments reveal that fueling from the midplane not only helps to couple waves from nearby antennas like in other devices, but also has an impact on the scrape-off layer (SOL) density in regions that are not magnetically connected to the valves. Localized midplane nozzle valves allow similar (in WEST) or better (in EAST) coupling compared to poloidally distributed valves. Core density control requirements for long-pulse operation, in particular in L-mode regime, however limit the amount of gas that can be injected. During ICRH impurities can contaminate the plasma up to a level detrimental for the operation, e.g. up to 100% of ICRH power can be radiated on WEST in certain high power conditions. In WEST, tungsten (W) production measured by visible spectroscopy increases on all the observed objects during ICRH compared to a reference phase without ICRH. On some components (antenna side limiters, baffle, divertor) the rise is larger than with a similar LH power. The relative contribution of each object and physical process (RF-sheaths, fast ion ripple losses) to core contamination yet remains poorly known. Comparing antenna limiters with W-coating vs low-Z materials would help quantifying the role of these components. In EAST, the core W content, measured by EUV spectroscopy in presence of divertor sources only, is correlated with the total injected power, either from ICRH or LH. Since 2018 the LH guard limiter tiles were W-coated. Their contribution to the core W content appears more important than divertor sources when two-strap ICRH antennas magnetically connected to W components at the midplane is powered, compromising high performance operations. [ABSTRACT FROM AUTHOR]

HIRFL-CSR, the project that was proposed to upgrade the HIRFL facility, is a multifunctional Cooling Storage Ring (CSR) system, consisting of a main ring (CSRm) and an experimental ring (CSRe). The heavy ion beams from the HIRFL will be injected, accumulated, cooled and accelerated to high energy in the CSRm, then fast-extracted to produce radioactive ion beams (RIB), highly-charged stage ions, or slow-extracted to do experiment. The secondary beams will be accepted by CSRe and used for internal-target experiments of the high sensitive and high precision spectroscopy with cool beam. CSR project was started in end of 1999 and finish in the end of 2004. The period from beginning of 2000 to the summer of 2001 is the time for the building construction, fabrication design, prototype experiments. In this paper, the outline and status of the project will be reported. [ABSTRACT FROM AUTHOR]

Electron cooling devices for HIRFL-CSR were under construction through collaboration between BINP and IMP[l]. The main parameters, design points and progress of the cooler devices will be presented. The electron motions in the gun region, adiabatic expansion region, toroid region and collector region were simulated with the help of numerical calculation. Cooling times of the typical heavy ions with injection energy were calculated with aid of the code. The prototypes of solenoid coils at the cooling section were fabricated and measured, the results show that the transverse components of the magnetic field for single coil is less than 2x 10[sup -4]. [ABSTRACT FROM AUTHOR]

CSR, a new Cooler-Storage-Ring project, is the postacceleration system of the Heavy Ion Research Facility in Lanzhou (HIRFL). It consists of a main ring (CSRm) and an experimental ring (CSRe). From the HIRFL cyclotron system the heavy ions will be accumulated, cooled and accelerated in the CSRm, then extracted fast and injected into the CSRe for many internal-target experiments with electron cooling. The experimental ring (CSRe) will be operated with three lattice modes for different experiments. The details of the lattice for the two rings will be described in this paper. [ABSTRACT FROM AUTHOR]