Axion searches with the storage ring EDM method

Abstract

The axion-gluon coupling induces an oscillating electric dipole moment (EDM) in nucleons. The oscillating EDM can be detected using a storage ring EDM method with resonance between the g-2 precession and the oscillating EDM frequencies. A frequency range from mHz to 100 MHz can be scanned using the resonance method and one below mHz down to about 10−9 Hz can be searched parasitically with the frozen spin method. The estimated sensitivity is at the level of 10−30 e · cm or higher. No experiment has accessed the proposed frequency range at such high sensitivity until now. In this study, we present the experimental method and compare the sensitivity with other experiments.