EXPLORATION TECHNOLOGY USING COSMIC RAY MUONS APPLIED TO INTERNAL STRUCTURE OF RIVER EMBANKMENTS AND EVALUATION OF THE PERFORMANCE OF SMALL DETECTORS

We are developing technology to explore the internal structure of river embankments with greater exploration depth and spacial resolution than conventional method. The geometric shape of the embankment was reconstructed by the observation data from the sluiceway. The density distribution inside the embankment was estimated with a resolution of 1 m × 1 m using tomographic inversion. In addition, we developed two small semiconductor detectors to save space and labor, and considered the observation accuracy for their applicability to river embankments. We confirmed that two observations were equivalent when the detector-housing temperature difference was kept within ±1°C except for a sudden change of the detector housing temperature.