High-beta section of a muon linac for the measurement of the muon g-2/EDM at J-PARC

Kondo, Yasuhiro   ; Hasegawa, Kazuo; Otani, Masashi*; Mibe, Tsutomu*; Yoshida, Mitsuhiro*; Kitamura, Ryo*

A muon linac development for a new muon g-2 experiment is now going on at J-PARC. Muons from the muon beam line (H-line) at the J-PARC MLF are once stopped in an silica aerojel target and room temperature muoniums are evaporated from the aerogel. They are dissociated with laser (ultra slow muons), then accelerated up to 212 MeV using a linear accelerator. For the accelerating structure from 40 MeV, disk-loaded traveling-wave structure is applicable because the particle beta is more than 0.7. The structure itself is similar to that for electron linacs, however, the cell length should be harmonic to the increase of the particle velocity. In this paper, the beam dynamics design of this muon linac using the disk-loaded structure is described.