Application of a Pulsed Neutron Transmission Method to a Cultural Heritage Study

Abstract

Pulsed neutron transmission imaging is a unique method that can give spatially dependent information on physical values of materials, such as crystallographic characteristics, elements, magnetic field, and so on. These data are obtained by analyzing the transmission spectra dependent on the neutron wavelength observed at each pixel of a 2-D position sensitive detector. We applied this method to cultural heritage samples. As test samples, we have studied Japanese swords. Three of them are fragments of swords with different areas and ages and the fourth is a full size one. We found that there were differences in texture and crystallite size among fragment samples, and the quenched area was clearly demonstrated in the full size sword. Furthermore, a Chinese coin was studied, and major elements and differences in crystallographic characteristics in the coin were indicated. The results indicated that the pulsed neutron transmission method can nondestructively give information that cannot be easily obtained by other methods.