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In order to meet the heating requirement of EAST tokamak, ion cyclotron range of frequency (ICRF) heating is utilized as one of the main auxiliary heating methods, which plays an important role in coupling radio frequency (RF) power into the plasma. As a member of plasma facing components, ICRF antenna suffers the plasma radiation as well which is one of the causes of the thermal load on the antenna. Plasma radiation and RF thermal load during the operation of ICRF and thermal load caused by HALO current during vertical displacement event will contribute together to a huge thermal load on the surface of the antenna and consequently the structural stability and reliability of ICRF antenna will be affected. Therefore, cooling channels is needed to remove heat on the ICRF antenna. In this paper, cooling channels for straps of ICRF antenna are designed based on the thermal load on the antenna, and thermal-structural analysis of straps with cooling channels is also carried out by the finite-element method. [ABSTRACT FROM AUTHOR]

Chinese Academy of Sciences Institute of Plasma Physics and Massachusetts Institute of Technology Plasma Science and Fusion Center have been collaborating on experimental advanced superconducting tokamak (EAST). Presented in this paper are RF, disruption, and thermal stress analyses of EAST antennas. Analyzed are I port four-strap and B port $2 \times 2$ strap antennas, which are currently installed on EAST. As for RF analysis, scattering parameters are checked to make sure that the antennas are loaded, and then electric field parallel to magnetic field are checked to find out if they are below the permissible level. As for disruption analysis, mechanical stresses for both straps with the support box and Faraday screen are obtained. As for thermal stress analysis, temperature and thermal stress for a typical strap and a Faraday tube were presented. All analyses were performed by COMSOL commercial finite-element analysis software package version 5 or 5.2. [ABSTRACT FROM AUTHOR]

Extreme ultraviolet (EUV) radiation with wavelengths of 11-14 nm is seen as the most promising candidate for a new lithographic technology. Compared with synchrotron radiation sources and laser-produced plasmas, gas discharge-produced plasma sources for EUV radiation are expected to offer lower cost of ownership. Using xenon, a broadband emission in the investigated wavelength range from 10 to 17 nm is observed. Very short current pulses, having a fast rise time of 85- or 140-ns duration and 23-kA amplitude, were applied across the xenon-filled Z-pinch capillary (3-mm diameter and 5-mm length) to produce EUV radiation. An EUV radiation from the Z-pinch plasma was characterized, which is based on the temporal behavior of EUV intensity and the pinhole images. Two maximum EUV radiations occur, which are sensitive to the xenon flow rate and the discharge current. The first radiation is relatively of short duration, while the second radiation lasts as long as the first period of the current flows. The EUV source size due to the first radiation is approximately 300 µm, i.e., half of the one due to the second radiation. [ABSTRACT FROM AUTHOR]