Japan's J-PARC Uses Negative Muon Non-Destructive Analysis to Reveal Gold-Rich Surface Structure of Nagoya Castle's Golden Shachi Scales
A joint research team comprising the High Energy Accelerator Research Organization (KEK), the J-PARC Center, the Nagoya Castle Research Center, and the National Museum of Nature and Science, among others, used the negative muon beam at the J-PARC Materials and Life Science Experimental Facility (MLF) to conduct non-destructive depth analysis on seven surviving scales of the golden shachi (ornamental dolphin-tiger fish) on Nagoya Castle's keep, confirming that five of the scales have a layered structure with high gold content within approximately 10 micrometers of the surface. The golden shachi on Nagoya Castle's keep was largely destroyed in the air raids of 1945, with some scales rescued and preserved to this day. Previously, researchers had examined these scales using X-ray fluorescence analysis, but the results showed that some scales with a bright golden appearance did not necessarily have a high average gold content.
2026-08-31
