Analysis system of submicron particle tracks in the fine-grained nuclear emulsion by a combination of hard x-ray and optical microscopy.

ABSTRACT

Analyses of nuclear emulsion detectors that can detect and identify charged particles or radiation as tracks have typically utilized optical microscope systems because the targets have lengths from several µm to more than 1000 µm. For recent new nuclear emulsion detectors that can detect tracks of submicron length or less, the current readout systems are insufficient due to their poor resolution. In this study, we developed a new system and method using an optical microscope system for rough candidate selection and the hard X-ray microscope system at SPring-8 for high-precision analysis with a resolution of better than 70 nm resolution. Furthermore, we demonstrated the analysis of submicron-length tracks with a matching efficiency of more than 99% and position accuracy of better than 5 µm. This system is now running semi-automatically.