title: Nondestructive elemental depth-profiling analysis by muonic X-ray measurement.
abstract: Elemental analysis of materials is fundamentally important to science and technology. Many elemental analysis methods have been developed, but three-dimensional nondestructive elemental analysis of bulk materials has remained elusive. Recently, our project team, dreamX (damageless and regioselective elemental analysis with muonic X-rays), developed a nondestructive depth-profiling elemental analysis method after a decade of research. This new method utilizes a new type of probe; a negative muon particle and high-energy muonic X-rays emitted after the muon stops in a material. We performed elemental depth profiling on an old Japanese gold coin (Tempo-Koban) using a low-momentum negative muon beam and successfully determined that the Au concentration in the coin gradually decreased with depth over a micrometer length scale. We believe that this method will be a promising tool for the elemental analysis of valuable samples, such as archeological artifacts.
authors.affiliation: †Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan.
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Ninomiya
authors.affiliation: ‡College of Liberal Arts, International Christian University, Mitaka, Tokyo 181-0015, Japan.
authors.forename: Michael K
authors.initials: MK
authors.lastname: Kubo
authors.affiliation: §Institute of Materials Structure Science, High Energy Accelerator Research Organization (KEK), Tsukuba, Ibaraki 305-0801, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Nagatomo
authors.affiliation: ∥Advanced Science Research Center, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195, Japan.
authors.forename: Wataru
authors.initials: W
authors.lastname: Higemoto
authors.affiliation: ∥Advanced Science Research Center, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195, Japan.
authors.forename: Takashi U
authors.initials: TU
authors.lastname: Ito
authors.affiliation: §Institute of Materials Structure Science, High Energy Accelerator Research Organization (KEK), Tsukuba, Ibaraki 305-0801, Japan.
authors.forename: Naritoshi
authors.initials: N
authors.lastname: Kawamura
authors.affiliation: §Institute of Materials Structure Science, High Energy Accelerator Research Organization (KEK), Tsukuba, Ibaraki 305-0801, Japan.
authors.forename: Patrick
authors.initials: P
authors.lastname: Strasser
authors.affiliation: §Institute of Materials Structure Science, High Energy Accelerator Research Organization (KEK), Tsukuba, Ibaraki 305-0801, Japan.
authors.forename: Koichiro
authors.initials: K
authors.lastname: Shimomura
authors.affiliation: §Institute of Materials Structure Science, High Energy Accelerator Research Organization (KEK), Tsukuba, Ibaraki 305-0801, Japan.
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Miyake
authors.affiliation: ⊥College of Engineering, Shibaura Institute of Technology, Saitama-shi, Saitama 337-8570, Japan.
authors.forename: Takao
authors.initials: T
authors.lastname: Suzuki
authors.affiliation: #Graduate School of Engineering Science, University of Electro-Communications, Chofu, Tokyo 182-8585, Japan.
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Kobayashi
authors.affiliation: ○J-PARC Center, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195, Japan.
authors.forename: Shinichi
authors.initials: S
authors.lastname: Sakamoto
authors.affiliation: †Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Shinohara
authors.affiliation: ⊗National Museum of Japanese History, Sakura, Chiba 285-8502, Japan.
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Saito