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Sugimura, Takashi*; Maruta, Tomofumi*; Hirano, Koichiro
Proceedings of 13th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.307 - 309, 2016/11
There is an upgrade plan of J-PARC (Japan Proton Accelerator Research Complex) Linac from currently operated beam parameters such as, beam current of 40 mA, beam pulse width of 0.5msec and repetition of 25 Hz, to 50 mA, 0.5msec and 50 Hz, respectively. To reduce beam loss during a beam acceleration is a must task to accelerate a high power beam. At J-PARC Linac, a beam from an ion source followed by RFQ (Radio Frequency Quadrupole) injected into a series of DTLs (Drift Tube Linac) through a MEBT1 (Medium Energy Beam Transport 1), where a beam matching and a beam pulse forming are carried out at the beam energy of 3 MeV. There are some locally activated spots in DTL area at the current beam power level so that some kind of mitigation measure is required. Beam simulation results show that the beam loss at the DTL area can be reduced if there is a pair of vertical beam collimators. This paper reports a design and fabrication status of new vertical collimators.
Kinsho, Michikazu; Ogiwara, Norio; Masukawa, Fumihiro; Takeda, Osamu; Yamamoto, Kazami; Kusano, Joichi
Proceedings of 2005 Particle Accelerator Conference (PAC '05) (CD-ROM), p.1309 - 1311, 2005/00
It was success to develop the radiation resistant components using for beam collimator. Turbo molecular pump could be operated more than 15 MGy of ray irradiation dose. Stepping motor developed at JAERI could be operated with good performance in the ray dose of more than 70 MGy. PEEK sheathed cables and connector have kept good performance during ray irradiation more than the dose of 10 MGy. It was cleared that the function of the heat pipe disappeared at 30 kGy ray irradiation dose.