<Advanced Energy Conversion Division> Advanced Energy Structural Materials Research Section

3-1. Research Activities in 202

Slow-positron beamline temperature rise reduction at Kyoto University Research Reactor

Temperature rises of a reactor-based slow-positron beamline at Kyoto University Research Reactor (KUR) were measured during reactor operation and solenoid-coil excitation. During KUR operation at 5 MW, the temperature of the top of the beamline reached 300 °C. This temperature which is close to the melting point (321 °C) of Cd was used to enhance positron generation. On the other hand, the temperature of the flange supporting the beamline was approximately 50 °C and it was sufficiently low in terms of the strength of the beamline. The temperature of the top of the beamline was successfully reduced to 240 °C by introducing a He gas flow around the vacuum duct of the beamline. Beamline temperatures calculated using a finite element method were in agreement with measured temperatures. Such calculation is useful for future experiments with longer or irregular KUR operation

Development of multi-channel electron spectrometer

Copyright 2010 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in Review of Scientific Instruments, 81(10), 10E535, 2010 and may be found at http://dx.doi.org/10.1063/1.348510

Effect of self-ion irradiation on hardening and microstructure of tungsten

AbstractThe irradiation hardening and microstructures of pure W and W–3%Re for up to 5.0 dpa by self-ion irradiation were investigated in this work. The ion irradiation was conducted using 18 MeV W6+ at 500 and 800°C. A focused ion beam followed by electro-polishing was used to make thin foil specimens for transmission electron microscope observations. Dislocation loops were observed in all the irradiated samples. Voids were observed in all of the specimens except the W–3%Re irradiated to 0.2 dpa. The hardness was measured by using nanoindentation. The irradiation hardening was saturated at 1.0 dpa for pure W. In the case of W–3%Re, the irradiation hardening showed a peak at 1.0 dpa. The correlation between the microstructure and hardening was investigated

Absolute calibration of imaging plate for GeV electrons

Copyright 2008 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in Review of Scientific Instruments, 79(6), 066102_1-066102_3, 2008 and may be found at http://dx.doi.org/10.1063/1.294021

Characterization of preplasma produced by an ultrahigh intensity laser system

Copyright 2004 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in Physics of Plasmas, 11(8), 3721-3725, 2004 and may be found at http://dx.doi.org/10.1063/1.176077