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We captured single shot images of ZnO emission patterns originating from excitation with the EUV laser at Japan Atomic Energy Agency (JAEA). The EUV laser was focused to a spot size of 1~\mu \m on the ZnO crystal by a Fresnel Zone Plate (FZP). The FZP was shifted along the propagation direction of the EUV beam, essentially changing the spot size at the ZnO surface. The emission pattern was detected by a magnifier. The waist radii were determined from the fitting curve as 5.0~\mu \m along the horizontal axis and 4.7~\mu \m along the vertical axis. We also evaluated the spatial resolution of the magnifier, which consists of a Schwarzschild mirror, two lenses and a camera lens to be about 4~\mu \m. These results suggest that the ZnO crystal has sub-micron spatial resolution when used as an in-situ imaging device for the diagnostics of EUV/X-ray sources. [ABSTRACT FROM PUBLISHER]

Scintillation properties of Ce^3+-doped 20Al(PO3)3- 80LiF glasses were investigated in order to seek a candidate for down-scattered neutron scintillator in nuclear fusion diagnostics. The decay constant of \ APLF80 + 3Ce with 5.5 MeV alpha particles from ^241Am radioisotope excitation was measured to be 32.1 ns. Moreover, sufficiently low afterglow decay profile and improved light output of \ APLF80 + 3Ce were experimentally demonstrated. [ABSTRACT FROM PUBLISHER]

We show that a hydrothermal method-grown ZnO is a potential material of an imaging device for soft X-ray laser diagnostics. The beam profile of a soft X-ray laser was evaluated by characterizing the exciton emission patterns of ZnO. The single shot image of emission patterns is clear enough to monitor the evolution of the beam radius around the focal point. By plotting the emission pattern radii at each position, the beam profile of the Ni-like Ag ion plasma laser was estimated from the waist radii as 29 \mum and 21 \mum in the horizontal and vertical axis, respectively. The divergence angle was estimated to be around 7.2 mrad and 11 mrad in the horizontal and vertical axis, respectively. The beam quality evaluated from the M^2 factor was 47 along the horizontal axis and 50 along the vertical axis. Spatial resolution of the magnifier was estimated to be 6 \mum and is expected to improve by optimizing the optics of the magnifier and using a telescope. Our results would enhance the use of ZnO as a high-spatial resolution in-situ imaging device that would play a crucial role in the development and application of soft X-ray light sources. [ABSTRACT FROM PUBLISHER]

Scintillation properties of Pr3+-doped 20Al(PO3)3-80 LiF glasses melted in N2 were investigated to seek a candidate for a scattered neutron scintillator in nuclear fusion diagnostics. The fluorescence lifetime of the sample with 217 nm ultraviolet femtosecond pulse excitation was measured to be 19.5 ns. More importantly, the fluorescence lifetime with alpha particles from 241Am radioisotope excitation was determined to be 6.7 ns. Based on our material design strategy, we have successfully developed the fast response time praseodymium-doped 6Li glass scintillator for scattered neutron diagnostics. [ABSTRACT FROM AUTHOR]