A fabrication of low power distribution system for muon $g-2$/EDM experiment at J-PARC

Abstract

The J-PARC muon $g - 2$/EDM experiment aims to measure the muon magnetic moment anomaly $a_{\mu} = (g -2) / 2 ~ $ and the muon electric dipole moment (EDM) $d_{\mu}$. The target sensitivity for $a_{\mu}$ is a statistical uncertainty of $450 \times 10^{-9}$, and for $d_{\mu}$ it is $1.5 \times 10^{-21}$ $e \cdot \rm{cm}$. The readout electronics require a DC to DC converter to provide 1.5 V and 3.3 V electric voltage within a specific environment. To capture the positron decay from the muon, the detector components are placed in the muon storage area where a 3 T magnetic field is applied in a vacuum. The extra magnetic field from the converter should be less than 30 $\mu$T to reach the aforementioned sensitivity on $a_{\mu}$. In addition, the electric field produced by the converter has to be as small as 1 V/m to also reach the target sensitivity on $d_{\mu}$. For this purpose, we develop a step-down converter. We discuss the development process and the performance of our DC to DC converter for the J-PARC muon $g - 2$/EDM experiment.