Increase of the beam intensity of high-intensity proton accelerator

We are carrying out the research continuously to improve the beam intensity of the J-PARC high-intensity proton accelerator.

Purpose and Vision

The most important feature of J-PARC accelerator is the enormous power of the accelerated beam. Currently, the beam intensity is getting stronger steadily aiming at the design value. It has to take care in the operation to minimize the loss of the beam because the beam intensity is so high that the amount of the lost beam is huge even if the ratio of that to the total beam is small. The places where the beam is lost frequently are the beam transport line, the beam injection section and the beam extraction section for the experiments. Purpose of the current research is to improve the capture and extraction efficiency of the beam at the places described just before. Not only the DC magnet but also the pulse magnet plays an active part at the injection and extractionsections. The study in order to increase the beam intensity is progressed continuously by the research on integrated system with a focus on these magnets.


J-PARC accelerator is composed of the linear accelerator, which accelerates the negative hydrogen ion, the rapid cycle synchrotron (RCS) and the main ring synchrotron (MR). MR is operated by the pulse mode with the repetition period of a few seconds. J-PARC accelerator is designed to increase the beam energy gradually so as to obtain the high intensity beam. Beam from the linear accelerator are accelerated in the RCS and it is used for the study of life and material science. Also part of the beam of the RCS is injected into MR, and is used in the experiments of particle physics and nuclear physics.

WEB page related

J-PARC Http://
J-PARC accelerator

Research facility related

J-PARC accelerator