Speaker
Description
Searches of electric dipole moments (EDM) of charged particles
in pure magnetic rings, such as COSY, or electrostatic and hybrid
magnetic-electric storage rings, planned in the future, require new
methods to disentangle the EDM signal from the large background
produced by magnetic dipole moments. In these experiments, the
sources of systematic background are in-plane magnetic fields. It is
important to distinguish the origins of the in-plane magnetic fields,
which could be produced intentionally by vertical orbit correction to
keep the beam on a closed path, or unintentionally due to the align-
ment errors of the magnets. We propose to use the method of spin
tune mapping to determine the relative importance of the two origins. At
the first stage, the model of COSY should be verified for the spin tune
shifts when vertical three-steerer closed-orbit bumps are applied. At
the second stage, the spin tune responce to vertical orbit correction in
the arcs will testify its contribution to the systematic background.
