Development of radiation resistant magnets for JHF/J-PARC project

A series of the R&D works on the radiation resistant magnets for the Japan Hadron Facility (JHF) project has been continued at the High Energy Accelerator Research Organization (KEK). The JHF is a high-energy part of the Japanese high intensity Particle Accelerator Research Complex (J-PARC), which is Japanese next-generation high-intensity accelerator project. The main JHF accelerator is the 50 GeV proton synchrotron and will provide high intensity 15/spl mu/A proton beam for various nuclear and particle physics experiments. This time, the actual sized completely-inorganic radiation-resistant quadrupole magnet, designed for the 50 GeV proton beam transportation, was manufactured successfully by using mineral insulation magnet cable (MIC). The assembling procedure and the test results are presented in this issue.

I. Introduction

The construction work of Japan Hadron Facility (JHF) [1] was initiated in 2002 as a part of Japanese high-intensity Particle Accelerator Research Complex (J-PARC) project [2]. The main accelerator of the JHF is the 50 GeV proton synchrotron (50 GeV-PS) whose beam intensity reaches 15 , i.e., the beam power of 750 kW. This enormous beam power is 10–100 times larger than that of existing accelerators of this energy range and will be upgraded to 4 MW in the future. The main usage of this high-power 50 GeV proton beam is the intense production of kaons, pions, and many other unstable and/or rare elementary particles such as antiprotons in order to promote the drastic progress of both nuclear and particle physics experiments. The neutrino beam facility also will be constructed for the long baseline oscillation experiments Fig. 1. JHF and J-PARC at Tokai campus of JAERI. NP-HALL is the experimental area for the nuclear particle physics and is the JHF. Neutrino beam facility is completely underground and can not be seen.