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ブランケット構造材料として開発された低放射化フェライト鋼の使用温度の低温側は573 K近傍であり、ここでは数dpa程度の中性子照射損傷量にて著しく照射硬化・脆化することがわかっており、照射後引張試験における正確なひずみ計測はブランケット設計活動において重要である。照射後引張試験は微小試験片を利用するため一般的なひずみ計を利用することはできない。そこでこれまではクロスヘッドの変位から計算される公称ひずみが代替されてきたが、これは試験片の標点間の変形以外の影響、例えば、肩部、冶具、そして、試験機一部の変形などを含んでいた。そこでは本研究はビデオカメラを用いて試験片の標点間部の画像を撮影してより正確にひずみを計測することができる技術の開発を目的とした。, 第12回核融合エネルギー連合講演会

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Pulsating auroras (PsAs) are thought to be generated by precipitating electrons scattered by lower‐band chorus (LBC) waves near the magnetic equator. One‐to‐one correlation between the LBC intensity and the PsA intensity has been reported. Electrostatic electron cyclotron harmonic (ECH) waves can also scatter electrons. However, direct correlation between ECH and PsA has not been reported yet. In this study, using a coordinated Exploration of energization and Radiation in Geospace (Arase) satellite and ground‐based imager observation, we report that not only LBC but also ECH have correlation with PsA. We estimated the precipitating electron energy by assuming that the time lag when the cross‐correlation coefficient became the highest was travel time of electrons from the modulation region. We found that the estimated energies show reasonable values as the cyclotron resonance energy of each wave.

We investigate the acceleration and transport of planetary ions within Kelvin-Helmholtz (KH) vortices that develop in the magnetospheric flanks of Mercury, using single-particle trajectory calculations in a field model obtained from MHD simulations. Due to the presence of heavy ions of planetary origin (e.g., O+, Na+, and K+) following ionization of exospheric neutrals and the complicated field structure during the KH vortex development, the scale of electric field variation may be comparable with ion gyration motion. Therefore ions may experience non-adiabatic energization as they drift across the magnetopause. In this study, we consider realistic configurations for both dawn and dusk magnetospheric flanks, and we focus on the effect of the spatial and temporal variations of the electric field magnitude and orientation along the ion path on the ion dynamics. We show that the intensification rather than the change of orientation is responsible for large non-adiabatic energization of heavy ions of planetary origin. This energization systematically occurs for ions with low initial energies in the direction perpendicular to the magnetic field, the energy gain being of the order of the energy corresponding to the maximum ExB drift speed, ɛmax, in a like manner to a pickup ion process. It is also found that ions that have initial energies comparable to ɛmax may be decelerated depending upon gyration phase. We find that ions with initial perpendicular energies much larger than ɛmax are little affected along the ion path through KH vortices. By comparing dynamical regimesin the dawn versus dusk regions, and also by considering different IMF directions, we show that the ion transport across the magnetopause is controlled by the orientation of the magnetosheath electric field and that the rate of energization depends upon the scale of KH vortices versus Larmor radii.