- Inelastic/Quasielastic Neutron Scattering
- Diffraction
- SANS/Reflectometry
- Imaging
- Neutron-Nuclear Reaction
- Muon
Requirements on radiation safety training and medical examination for hands-on training
- The participants will be requested to submit radiation worker registration forms, in which the radiation protection officer in your institute or university will write your latest records of radiation safety training and medical examination for radiation workers.
- The deadline of the radiation worker registration form is 15 October 2025
- Your latest records of radiation safety training and medical examination for radiation workers should NOT be older than the following dates.
- Radiation safety training : 16 October 2024
- Medical examination for radiation workers (date depend on your position):
- 16 October 2024 (Students/Employee from foreign institutes, Students of Japanese institutes)
- 16 April 2025* (Employee of Japanese institutes)
- Please consult radiation protection office of your institute or university in advance to check those records. If you have any questions regarding the radiation worker registration, please contact us by email (nm-school[at]cross.or.j ).
- Details for registration as radiation workers will be announced after the selection of participants has been completed.
* Note that if you had the latest medical examinations for radiation workers in early April 2025, it will be valid for 6 months for the application to MLF. If you want to use this record for this school, please submit the radiation worker registration form before 6 months have elapsed since the latest medical examination.
Inelastic/Quasielastic Neutron Scattering
Dynamics study by inelastic neutron scattering
Inelastic neutron scattering is an experimental method that is used to observe micro-vibration (dynamics) of atoms and spins in a material. By observing the difference in energy between the incident and scattered neutrons, the magnitudes, distances, and directions of the forces acting between the atoms or spins in the material can be determined.
In this course, students will learn how to measure collective vibrations of atoms (phonons) or spins (magnons) in a single crystal as a function of momentum and energy by inelastic neutron scattering using the chopper spectrometer 4SEASONS. By analyzing the data, students will learn what kinds of forces act between atoms or spins and how they affect the macroscopic properties.
Proton conduction studied by quasielastic neutron scattering
Quasielastic neutron scattering enables us to observe ion, atomic, and spin dynamics over a wide dynamic range from picoseconds to nanoseconds.
In this course, participants will learn how to prepare and measure samples (Nafion as a proton exchange membrane), and how to analyze data.
Study on Neutron Spin Echo Technique with Neutron Resonance Spin Flippers
Neutron spin echo (NSE) spectroscopy explores the microscopic dynamics of condensed matter ranging from sub nanoseconds to hundred nanoseconds in nanometer scale. BL06 VIN ROSE at MLF provides unique experimental opportunities with time-of-flight (TOF) neutron resonance NSE instruments.
In this course, participants will learn the principle of NSE spectroscopy and what kind of dynamical information can be obtained through a hands-on training of data analysis of a soft matter sample. Especially, the basic handling of neutron-spin polarization with the resonance spin flippers and their applications for TOF-NSE technique will be experienced.
The Dynamics in a Harmonic Oscillator Observed via POLANO
The application of the time-of-flight (TOF) method has only been realized in recent years. Comparing to a reactor based neutron source, The TOF has a huge advantage in investigating wide area of energy E and momentum Q. In the TOF inelastic scattering it can be detected that dynamic properties of each physical degrees of freedom like spins, orbitals, charges and lattice vibrations. These dynamical structures yield deep understandings of the variety of microscopic mechanism in materials.
In this training course of POLANO we focus on the basic skills for the inelastic experiment with TOF method and measure the dynamic properties of ZrH2, a text-book harmonic oscillator. You will learn about an essence of quantum mechanics of modern and basic physics and how the inelastic neutron scattering can be useful to investigate the condensed matter physics.
Diffraction
Structural Phase Transitions in BaTiO₃ Studied by High-Resolution Neutron Powder Diffraction
The BL08 SuperHRPD at J-PARC MLF is a world-class time-of-flight powder diffractometer, optimized for ultra-high-resolution structural measurements. Situated ~100 m from a decoupled poisoned moderator, SuperHRPD has achieved a record resolution of Δd/d≈0.035%. This extreme resolution enables extremely precise determination of lattice parameters, subtle symmetrical distortions, and light-element positions in materials. Neutron diffraction on SuperHRPD can accurately locate light atoms (such as hydrogen or oxygen) in a crystal structure, which is often complementary to X-ray data. These capabilities make SuperHRPD ideal for studying temperature-dependent structural transitions and ferroelectric materials.
In this course, participants will carry out neutron powder diffraction experiments on BaTiO₃ powder below 300 K, capturing its well-known ferroelectric phase transitions (tetragonal ↔ orthorhombic ↔ rhombohedral). Under the guidance of instrument scientists, each student will help set up the experiment, collect neutron diffraction data on SuperHRPD, and then analyze them using the Z-Rietveld software package. The focus is getting to learn the entire workflow and focusing on how neutron diffraction can reveal changes in the crystal structure of BaTiO3. Because neutron diffraction is sensitive to light elements like oxygen, by tracking the movement of oxygen atoms, which are hard to see with X-rays alone, we can learn about the changes in the material's structure. Students will prepare short presentations summarizing their findings, thereby reinforcing the learning objectives and fostering communication skills.
SANS/Reflectometry
Contrast SANS measurements of nanoparticles
In the hands-on training at BL15, students will learn about the pulsed small-angle neutron scattering (SANS) instrument, data reduction methods, and various sample environment devices, as well as perform measurements of standard samples and solvent contrast variation SANS for nanoparticles.
Imaging
Visualizing the inside of objects by neutron imaging
Neutron imaging is a nondestructive observation technique utilizing the neutron's unique characteristics, such as a high penetration power compared with X-rays and a high sensitivity to light elements like hydrogen, lithium, or boron. Consequently, this technique is applied to visualize internal 2D/3D structure of massive objects or the water content/behavior inside objects. Usage of pulsed neutrons provides more characteristic features to neutron imaging. Since it is possible to analyze the neutron energy by Time-of-Flight technique, the energy-dependent images can be easily and precisely obtained. This is referred to as “Energy-resolved neutron imaging”, which enables us to image spatial distributions of crystallographic, elemental, thermal, or magnetic information.
In this course, students will be introduced to the basics of the conventional neutron imaging (neutron radiography and tomography) and advanced neutron imaging techniques using the pulsed neutron beam. And students will conduct some demonstration experiments and data analysis using the RADEN instrument (BL22).
Neutron-Nuclear Reaction
Measurement of neutron total cross section
Detailed measurements of nuclear reactions between neutrons and nuclei can be performed. Detectors for measuring gamma rays emitted in neutron capture reactions (HPGe and NaI detectors) are installed, and neutron detectors for measuring neutrons transmitted through the sample are also available. Using these detectors, studies such as measurements of neutron capture cross sections, total cross sections, and so on are conducted.
In this course, we will measure the neutron transmission rate of a gold sample and derive the total cross section through data analysis. An analysis program will be developed using CERN ROOT, and the results obtained will be compared with previous measurements.
Muon
Positive muon spin relaxation (μSR)
S1 (MLF) Positive muon spin relaxation (μSR) When a positive muon stops at an interstitial site within a material, it observes the magnetic fields of its environment and exhibits Larmor spin precession. By measuring the decay positrons emitted from muons, the time-dependent behavior of the muon spin in the material can be investigated. This technique is called positive muon spin relaxation (μ SR). μSR provides information on the magnetic properties of a material, including magnetism, superconductivity, and the hydrogen state within the material, as the muon acts as a light hydrogen isotope. In contrast to neutrons, muons are local magnetic probes in real space with a unique time scale, making them powerful tools for probing spin relaxation phenomena. In this course, students will perform μSR measurements using the spectrometer and receive instruction on data analysis. Introductory lectures on μSR and other muon measurement techniques will also be given as part of the school. This experiment will be conducted at the S1 area.
Techniques Using Negative Muons
Negative muons are useful tools for identifying elements inside materials. When a muon is captured by a nucleus, it forms a muonic atom. The muon orbits close to the nucleus and emits muonic X-rays with energies much higher than normal X-rays. These X-rays allow non-destructive, deep analysis. This method is valuable for studying cultural artifacts without damage. At MLF, J-PARC, muonic X-rays were used to examine a 400-year-old Japanese gold coin, revealing details of ancient metalwork. Another technique uses muon lifetimes. A free muon lives for 2.2 microseconds, but in atoms, the lifetime shortens depending on the element—e.g., 2.0 μs for carbon, 200 ns for iron. This allows detection of small amounts of elements, such as carbon in traditional Japanese swords. This course introduces both techniques. Participants will also attend introductory lectures on μSR using negative muons.
Ultra-Slow Muon Spin Spectroscopy
Ultra-Slow Muon Spin Spectroscopy Muons have extensive applications in materials science as spin-polarized quantum beams. Muon spin rotation/relaxation/resonance (μSR) is an experimental technique used to implant muons into materials for probing local magnetic fields. The muon beams primarily used in μSR experiments, known as surface muons, are obtained from pion decays at the surface of the production target. Surface muons exhibit near-perfect polarization and monochromaticity. Nevertheless, due to their high energy of 4 MeV, measurements on thin samples using a surface muon beam are challenging. In this regard, low-energy muons are advantageous for measurements of thin-film samples and studies of interfaces within materials. The Ultra-Slow Muon (USM) beamline at MLF MUSE provides a low-energy muon beam via laser ionization of thermal muonium in a vacuum. At the U1A experimental area, a muon spin spectrometer is located on a high-voltage platform to control the muon implantation energy from sub-keV to 30 keV. USMs can be selectively implanted at (sub-)surfaces and interfaces within materials, enabling depth-resolving μSR. Furthermore, the temporal width of the USM beam is only a few nanoseconds, significantly narrower than that of the pulsed proton beam, which allows for the study of dynamics over a wide frequency range. In this course, participants will learn about the USM generation mechanism and transport scheme, and gain hands-on experience with USM-μSR experiments on a thin-film sample.
