Neutron & Muon School — U1A Hands-on Training

The Neutron and Muon School is an international training school for graduate students, postdoctoral fellows, and early-career researchers. Participants learn the fundamentals of neutron and muon techniques through lectures and hands-on training at J-PARC MLF and, in recent editions, JRR-3. This page focuses on the U1A muon hands-on program.

2025

SchoolThe 14th AONSA Neutron School / The 9th Neutron and Muon School
DateNov. 17–21, 2025
Hands-onU1A, J-PARC MLF
ResultU1A team received the second-place presentation award.

Hands-on training page  |  Event report

U1A Program : 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.

2024

SchoolThe 8th Neutron and Muon School
DateDec. 9–13, 2024
Hands-onU1A, J-PARC MLF
NoteU1A was included among the muon training instruments; due to an MLF facility issue, prepared data sets were used for analysis instead of new beam data.

Event report

U1A Program : 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 method to implant muons into materials for probing local magnetic fields. The muon beams primarily used in μSR experiments, so-called surface muons, are obtained from pion decays at the surface of the production target. The 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 with thin-film samples and studies on interfaces inside materials.

The ultra-slow muons (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 on surfaces and interfaces in materials, enabling depth-resolving μSR. Furthermore, the time width of the beam is a few ns, much narrower than that of the pulsed proton beam, so the frequency range of observable dynamics is wide. In this course, participants will learn the mechanism of USM generation, the transport scheme, and experience USM-μSR with a thin-film sample.

2023

SchoolKEK-IINAS School / The 7th Neutron and Muon School
DateDec. 18–22, 2023
Hands-onU1A, J-PARC MLF
FormatHands-on training included instrument operation, sample handling, beam measurement, and data analysis across participating beamlines.

Event report

U1A Program : Ultra-Slow Muon Spin Spectroscopy

Muons find extensive application in materials science as spin-polarized quantum beams. Muon spin rotation/relaxation/resonance (μSR) is an experimental method to implant muons into materials for probing local magnetic fields. The muon beams primarily used in μSR experiments are obtained from pion decays at the surface of the production target. These beams are so-called surface muons and 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 have advantageous for measurements with thin-film samples and studies on interfaces.

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. USMs can be selectively implanted on surfaces and interfaces in materials, enabling depth-resolving μSR. Furthermore, the time width of the beam is much narrower than that of the pulsed proton beam, so the frequency range of observable dynamics is wide. In this course, participants will learn the mechanism of USM generation, the transport scheme, and experience USM-μSR with a thin-film sample.

2022

SchoolThe 6th Neutron and Muon School
DateDec. 12–16, 2022
Hands-onU1A, J-PARC MLF
FormatThe school resumed on-site practical training after the pandemic period; U1A and S1 were used for muon hands-on training.

Event report

U1A Program : Ultra-Slow Muon Spin Spectroscopy

At J-PARC MLF, MUSE provides the world-highest flux of pulsed muon beams. U-Line, one of the four beamlines in the facility, features an intense surface muon beam from Super-Omega and Ultra-Slow Muon (USM) by laser ionization of thermal muonium. The beamline has two branches: U1A for μSR studies using USM and U1B for transmission muon microscope.USMs can be selectively implanted on surfaces and interfaces in materials, enabling depth-resolving muSR. Furthermore, the time width of the beam is much narrower than that of the pulsed proton beam, so the frequency range of observable dynamics is wide. The generation of USM brings together advanced technologies in various fields, and is an interdisciplinary study that combines laser physics, atomic physics, ion transport optics, and surface science. In this course, participants will learn the mechanism of USM generation and the transport scheme, and experience USM-muSR through spectrometer data analysis.