Centers & Labs

RIKEN Nishina Center for Accelerator-Based Science


Team Leader: Hideaki Otsu (D.Sci.)
Hideaki  Otsu(D.Sci.)

In collaboration with research groups in and outside RIKEN, the team designs, develops and constructs the SAMURAI spectrometer and relevant equipment that are and will be used for reaction experiments using RI beams at RI Beam Factory. The SAMURAI spectrometer consists of a large superconducting dipole magnet and a variety of detectors to measure charged particles and neutrons. After the commissioning experiment in March 2012, the team prepared and conducted, in collaboration with researchers in individual experimental groups, the first series of experiments with SAMURAI in May 2012. The team also provides basis for research activities by, for example, organizing collaboration workshops by researchers who are interested in studies or plan to perform experiments with the SAMURAI spectrometer.

Main Research Field

Mathematical and physical sciences


  • Unstable nuclei
  • Neutron drip-line
  • Weakly bound structure
  • Cluster structure on nuclei

Selected Publications

  1. J. W. Hwang, S. Kim, Y. Satou, et. al:
    "Single-neutron knockout from 20C and the structure of 19C"
    Phys. Lett. B 769, 503 (2017).
  2. Y. Togano, T. Nakamura, Y. Kondo, et. al.:
    "Interaction cross section study of the two-neutron halo nucleus 22C"
    Phys. Lett. B 761, 412 (2016).
  3. Y. Kondo, T. Nakamura, R. Tanaka, R. Minakata, S. Ogoshi, et. al.:
    "Nucleus O26: A Barely Unbound System beyond the Drip Line"
    Phys. Rev. Lett. 116 (2016) 102503.
  4. J. Yasuda, M. Sasano, R.G.T. Zegers, et. al.:
    "Inverse kinematics (p,n) reactions studies using the WINDS slow neutron detector and the SAMURAI spectrometer"
    Nucl. Instr. Meth. B376 (2016) 393-396
  5. H. Otsu, et. al:
    "SAMURAI in its operation phase for RIBF users"
    Nucl. Instr. Meth. B376 (2016) 175-179
  6. T. Nakamura, Y. Kondo:
    "Large acceptance spectrometers for invariant mass spectroscopy of exotic nuclei and future developments"
    Nucl. Instr. Meth. B376 (2016) 156-161
  7. R. Shane. A. B. McIntoshb., T. Isobe, et. al;
    "SπRIT: A time-projection chamber for symmetry-energy studies"
    Nucl. Instr. Meth. A784 (2015) 513
  8. T. Kobayashi, N. Chiga, T. Isobe, Y. Kondo, T. Kubo, K. Kusaka, T. Motobayashi, T. Nakamura, J. Ohnishi, H. Okuno, H. Otsu, T. Sako, H. Sato, Y. Shimizu, K. Sekiguchi, K. Takahashi, R. Tanaka, and K. Yoneda:
    "SAMURAI spectrometer for RI beam experiments"
    Nucl. Instr. Meth. B317, 294-304 (2013).
  9. Y. Shimizu, H. Otsu, T. Kobayashi, T. Kubo, T. Motobayashi, H. Sato, and K. Yoneda:
    "Vacuum system for the SAMURAI spectrometer"
    Nucl. Instr. Meth. B317, 739-742 (2013).
  10. H. Sato, T. Kubo, Y. Yano, K. Kusaka, J. Ohnishi, K. Yoneda, Y. Shimizu, T. Motobayashi, H. Otsu, T. Isobe, T. Kobayashi, K. Sekiguchi, T. Nakamura, Y. Kondo, Y. Togano, T. Murakami, T. Tsuchihashi, T. Orikasa, and K. Maeta:
    "Superconducting Dipole Magnet for SAMURAI Spectrometer"
    IEEE Trans. Appl. Supercond. 23, 4500308 (2013).

Contact information

2-1 Hirosawa,
Wako, Saitama
351-0198, Japan

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