Crystallographic analysis of metal cultural heritages is one of important neutron applications, since nondestructive analysis is desired. We have been studying Japanese swords using the pulsed neutron imaging, and obtained position dependent information of crystallite size, anisotropy and lattice spacing. The results coincide with destructive studies, which indicated that the method was useful for the metal artifacts.

It is said that traditional Japanese iron has good workability and is difficult to rust. The reasons for these characteristics lie in the raw materials, iron making technique, and iron manufacturing technique of ancient Japan. However, the details of those techniques are not clear as they were mainly kept secret. We have been studying the metallurgical microstructure of Japanese iron artifacts, such as a Japanese matchlock gun, by destructive methods and nondestructive methods using high-energy X-ray. Furthermore, recently we have started a nondestructive study of iron artifacts using pulsed neutron. In this paper, we describe the present status of our nondestructive study. The purpose of this work is to compare the results of destructive and nondestructive methods and to contribute to the advancement of the nondestructive study of iron artifacts. The final goal of our study is to analyze iron artifacts systematically by nondestructive methods, to clarify the metallurgical characteristics of iron artifacts, and to reveal the traditional Japanese iron making and forging techniques.

A new non-destructive multi-elemental analysis method using negative muon beam has been developed. This method is based on measurement of characteristic muonic X-rays emitted after muonic atom formation. Muonic X-rays are very hard because of a large mass of the muon, so elemental analysis for deeply inside of a bulk material is possible. In addition, because the muon stopping depth can be controlled by adjusting incident muon energy, three-dimensional analysis will be achieved. To develop this elemental analysis method, we performed muon irradiation experiment for two types of archeological samples; bronze artifacts (coin and mirror) for investigation of quantitative elemental composition and estimation of detection limit, and a gold coin (Tempo-koban) for demonstration of elemental depth-profiling without sample destruction.

We introduce the inelastic neutron and synchrotron X-ray scattering studies on the magnetic excitation in the electron-doped copper oxide. The recent development of state-of-the-art spectrometers at large facilities such as J-PARC enables us to study composite dynamics in the energy-momentum space arising from the interacting degrees of freedom. High-T_c copper oxide superconductor is exotic systems, in which the spin and charge degrees of freedom are coupled. We found the elongation of spin excitation by the electron-doping, which is quite different from the negligible doping effect in the hole-doped system. Therefore, there exists the electron-hole asymmetry in the observed spin excitation against the doping.

CO molecules taken up in clathrate hydrates with structures I and II show highly disordered arrangements, which are hard to analyze by classical methods for structure refinement adopting split-atom models. Rietveld refinements followed by maximum entropy method analyses from TOF neutron powder diffraction data of CO clathrate hydrates made it possible to visualize doughnut- and die-like distributions of CO molecules in 5¹² and 5¹²6⁴ cages, respectively.

The deuterization process of fcc Fe to form solid‒solution fcc FeD_x was investigated by in situ neutron diffraction measurements at high temperature and high pressure. In a completely deuterized specimen at 988 K and 6.3 GPa, deuterium atoms occupy the octahedral and tetrahedral interstitial sites with an occupancy of 0.532(9) and 0.056(5), respectively, giving a deuterium composition x of 0.64(1). During deuterization, the metal‒lattice expands approximately linearly with deuterium composition at a rate of 2.21 ų per deuterium atom. The minor occupation of tetrahedral site is likely driven by the intersite movement of deuterium atoms along the <111> direction in the fcc metal lattice. These results provide implications for the light elements in the Earth's core and the mechanism of hydrogen embrittlement of ferrous metals.

Neutron diffraction is the only method which can measure residual stresses inside materials at centimeter-order depth nondestructively. Residual strains can be derived from the diffraction peak shift, and residual stresses can be calculated by applying lattice strains measured in three orthogonal directions to the Hooke’s law. In addition, the neutron diffraction method can be utilized for evaluation of deformation behaviors of engineering materials by measuring microstructural factors such as microstrains, texture and dislocation density. Therefore, the neutron diffraction technique is very useful in the design and development of engineering components, as well as in studies on materials engineering. Here we show the principle of the neutron stress measurement and the engineering neutron diffractometers as well as some applications.

Introduction to the latest modern chopper spectrometers for pulsed neutron sources is shown. After coming up of recent high-performance pulsed neutron sources such as J-PARC, SNS and 2nd target station of ISIS, much progress have been achieved in technology regarding to chopper spectrometers in both hardware and software. A multi-E_i measurement based on repetition rate multiplication technique alters strategy of the measurements. Source pulse shaping provides opportunity precise measurements with high intensity. Current data analysis software enables us to access to the four dimensional space in energy and momentum transfers.

NOBORU was constructed at beam-line no. 10 (BL10) of the Materials and Life Science Experimental Facility (MLF) at J-PARC in 2007. The primary mission of NOBORU is facility diagnostics to study neutronic performance of Japan Spallation Neutron Source (JSNS). Validation methods of unique neutronics design features of JSNS are briefly reviewed.

The High Resolution Chopper Spectrometer (HRC) was installed and is being operated at BL12 of J-PARC/MLF to study condensed matter dynamics with high resolutions using relatively high energy neutrons. The Polarized Neutron Spectrometer (POLANO) is being constructed at BL23 to utilize polarized neutrons for dynamical studies. We hope that these two chopper spectrometers provide an opportunity to expand the observation area in inelastic neutron scattering experiments by using high energy neutrons and polarized neutrons with a good sample environment.

It is well known that neutron powder diffraction is very powerful tool for materials science and engineering. In J-PARC, six powder diffractometers are operating. In this paper, a brief introduction and specification for versatile powder diffractometer, iMATERIA, super high resolution powder diffractometer, SuperHRPD and special environment powder diffractometer, SPICA are shown and also some example taken from these diffractometers.

Accurate Neutron Nucleus Reaction Instrument (ANNRI) was designed for experiments using gamma-ray spectroscopy such as nuclear data, prompt gamma-ray analysis (PGA) and nuclear astrophysics. The instrument is equipped with two detectors that provide complementary information: Ge detectors, which offer higher energy resolution for gamma-rays, and NaI detectors, which allow us to use neutrons of higher energy. Other key components of the instrument, including double disk chopper, X stage collimator, filter unit, rotary collimator and auto sampler, are discussed. This paper gives an overview of recent results from experiments concerning nuclear data and PGA carried out using ANNRI. In the nuclear data research, we performed experiments of neutron-capture cross sections for long-lived fission products and minor actinides. In addition, we developed a new analytical technique that combines PGA and time-of-flight elemental analysis by using an intense pulsed neutron beam.