关键词: 氘含量与分布测量, 核反应分析, 微分反应截面, 面向等离子体材料

Abstract:

To fulfill the need of studying the deuterium retention in nuclear materials, the authors set up an NRA to analyze device with three channel detecting system based on 4.5 MV electrostatic accelerator in Peking University, and developed a multi-energies NRA method for quantitative depth profiling deuterium. With the simultaneous energy spectra of p and 4He created by the D (3He, p) 4He nuclear reaction, by adopting several different incident 3He+ energies (0.8?3.6 MeV), a reasonable better depth resolution and higher sensitivity in a larger analyzing depth could be obtained. The authors also measured differential cross-section of the 3He-D reaction at 135°. The relative accuracy of these data was better than ±3.9%. The initial measurement of concentration and depth profiles of D was carried out, using targets of implanted PC-W samples, as well as CMSIIW samples from a W-coated outer divertor tile of TOKAMAK AUG near the strike points. A ~6 μm analyzed depth could be obtained with a depth resolution less than 1.5 μm throughout the whole detecting range and a ~20 nm minimal resolution at the sample surfaces. The detection limit was around 5×1019 D/m2. Apart from the statistical and fitting error of NRA spectra, the NRA system had an experimental error of ±7.5% from the parameter measurement.

Key words: deuterium concentration and distribution, nuclear reaction analysis, differential cross-section, plasma facing materials