Low-power test of bridge coupler in disk-and-washer structure for muon acceleration

Kondo, Ayaka*; Iijima, Toru*; Sumi, Kazumichi*; Takeuchi, Yusuke*; Cicek, E.*; Ego, Hiroyasu*; Otani, Masashi*; Nakazawa, Yuga*; Futatsukawa, Kenta*; Mibe, Tsutomu*; Yoshida, Mitsuhiro*; Kondo, Yasuhiro   ; Morishita, Takatoshi  ; Iwashita, Yoshihisa*

A muon linear accelerator is under development at J-PARC for precise measurement of the muon anomalous magnetic moment (g-2) and electric dipole moment (EDM). Adisk-and-washer (DAW) structure is employed to accelerate muons from 30% of the speed of light (kinetic energy 4 MeV) to 70% (40 MeV) at 1296 MHz. The muon DAWconsists of tanks accelerating the muons and bridge couplers that couple the tanks and focus the beam using an internal quadrupole doublet. A bridge-coupler prototype is currently being fabricated and will be tested. This paper presents the design and performance evaluation of the bridge coupler prototype.