Gravitational Effects in Electrostatic Storage Rings and the Search for the Electric Dipole Moments of Charged Particles

Abstract

Spurious signals induced by curved spacetime in the gravity field of the rotating Earth in experiments on the search for the electric dipole moment of charged particles manifested by the spin rotation in pure electrostatic storage rings have been analyzed with the focus on effects of Earth’s rotation. It has been found that the rotation of the plane of an electrostatic storage ring together with the Earth generates a nonzero magnetic field. Locally in the storage ring, the spin precession frequency linear in Earth’s rotation is much higher than the frequency of the spin precession caused by the electric dipole moments. It has been argued that the integral spurious spin rotation for a particle on an ideal orbit is strongly suppressed because the contribution from Earth’s rotation is sign-alternating along the storage ring. A background signal quadratic in Earth’s rotation is finite but small.