Design of the beam transportation line from the linac to the 3-GeV RCS for J-PARC

Okawa, Tomohiro*; Ikegami, Masanori*

Proceedings of 9th European Particle Accelerator Conference (EPAC 2004), p.1342 - 1344, 2004/00

The accelerators for the High-Intensity Proton Accelerator Facility Project, J-PARC, consist of a 180-MeV linac, a 3-GeV RCS (Rapid Cycling Synchrotorn), and a 50-GeV MR (Main Ring). L3BT is a beam transport line from the linac to the RCS. To meet the requirement for the beam loss minimization, the L3BT does not only connect the linac to the 3GeV RCS, but also modifies the linac beam to be acceptable for the RCS. The required beam parameters at the injection point of the RCS are momentum spread 0.1 and transverse emittance 4 mmmrad. To achieve these beam qualities, the L3BT should have following functions: momentum compaction, transverse halo scraping and beam diagnostics. In this paper, results of the design and beam simulation of the L3BT are presented.