Dept. of Accelerator and Medical Physics


 The Accelerator Engineering Department manages the operation and maintenance of electrostatic accelerators in the MeV class, cyclotrons in the tens of MeV class. And heavy ion accelerators in the tens of thousands of MeV class, in terms of energy scale. It stably and reliably accelerates and supplies a wide range of beams, from protons to xenon, covering beam ranges from microns to tens of cm. These ion beams are used for research into biological radiation responses, with microbeams and neutrons, the production of radioisotopes that are familiar for their use in cancer diagnostics, cancer treatment with high-energy carbon beams, and other applications. Other than R&D into accelerators, beam controllers and other hardware suitable for these applications, the department works on software R&D for the generation and control, etc. of therapeutic beams that take into account biological effects on tumors and normal tissue. This research, and the technologies it develops, serves to raise the national standard of living in visible forms, such as real cancer diagnosis and particle beam cancer treatment.

Research Theme

The HIMAC heavy particle beam cancer treatment system

HIMAC is an abbreviation for “Heavy Ion Medical Accelerator in Chiba”, which is the world’s first specialized heavy ion cancer treatment facility. HIMAC consists of a primary accelerator (synchrotron) to accelerate carbon beams and other heavy particle beams to 800MeV of energy per nucleus, an injector (linear accelerator), and a treatment room in which to irradiate the patient.


The advancement of scanning irradiation for on-demand therapy

We are working to develop a high-speed 3D beam scanning irradiation method to achieve more advanced irradiation than previous methods, and combine that with “breath synchronized irradiation” to achieve a world-leading torso scanning irradiation system. We are also advancing research and development to use superconductor magnets to reduce weight, so that heavy particle beams can be used even from a rotating gantry that would allow irradiation from any desired angle in a 360° range. This advance can be expected to further reduce the physical burden on the patient, shorten the treatment time, and greatly enhance therapeutic effects.



Towards the realization of a “heavy particle beam cancer treatment to move the world forward”

We are working on various activities to promote the spread of heavy particle beam cancer treatments. These include human development of future medical personnel who will be involved in heavy particle beam cancer treatment, joint research using HIMAC, and collaboration and assistance for related agencies in Japan and overseas.

Support for the development and industrial application of irradiation and analysis technologies using electrostatic accelerators

The National Institute of Radiological Sciences has two tandem-type electrostatic accelerators. One is for element analysis and proton microbeam cell irradiation, and the other is for neutron beam generation.
We receive various requests from users, as research at these facilities progresses, and we are developing and realizing new technologies on that basis. The results of this effort include advancing PIXE technology to expand the range of elements that it can analyze, enhancing the speed of cell irradiation and the range that can be irradiated, and the development of neutron fields with narrow energy ranges.
The combination of these results and strong public relations activities is rapidly increasing the numbers of user requests from industry, as well as from universities and research agencies in Japan and overseas.
This facility will go on ambitiously tackling the development of new technologies that contribute to the advancement of science.

External view of SPICE (microbeam cell irradiation system). The picture above shows the irradiation room and the one below shows the beam line. With a 2µm beam size, this system can irradiate 10,000 cells per cell dish.

PIXE analysis result for a NIST SRM2783 standard sample. The red text indicates light elements that are newly analyzable. Other than these, it has also become possible to analyze elements such as F and U.

Research for the advancement of cyclotron accelerators

Cyclotrons are used in the production of radioisotopes (RI), and in fundamental research in the fields of physics and biology. RI production makes RI for molecular imaging, and also RI for targeted isotopes for drug research. The production of adequate quantities of RI requires the stable supply of high-quality, high-intensity beams. We are working on research towards more advanced cyclotrons, developing technologies for higher beam intensity and irradiation and diagnostic technologies to use with high-intensity beams.
We are also researching the use of RI produced with a cyclotron for heavy particle beam cancer treatment, to further enhance irradiation precision. We are advancing RI beam generation systems to that end.

Research Team

  • Advanced Particle Therapy System Research Team
  • Therapeutic Beam Research Team
  • Treatment System Research Team
  • Radiation Effect Research Team
  • Beam Delivery System Research Team
  • HIMAC Operation Section
  • Cyclotron Operation Section
  • Electrostatic Accelerator Operation Section

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4-9-1 Anagawa, Inage-ku, Chiba-shi, Chiba 263-8555, Japan Tel: +81-43-206-3025 (outside of Japan), or 043-206-3025 (in Japan)