Search for permanent Electric Dipole Moments of light ions (p, d, ³He) in storage rings
The Standard Model (SM) of Particle Physics fails to explain the reason for our very existence since it is not capable to account for the apparent matter-antimatter asymmetry of our Universe. Physics beyond the SM is required and is searched for by (i) employing highest energies (e.g., at LHC), and (ii) striving for ultimate precision and sensitivity (e.g., in the search for electric dipole moments (EDMs)). Permanent EDMs of particles violate both time reversal (T) and parity (P) invariance, and are via the CPT-theorem also CP-violating. Finding an EDM would be a strong indication for physics beyond the SM, and pushing upper limits further provides crucial tests for any corresponding theoretical model, e.g., SUSY.
For about half a century, neutron EDM (nEDM) measurements at many laboratories worldwide are trying to extend the already impressive experimental limits even further. Searches for EDMs of the proton, the deuteron, and of heavier nuclei bear the potential to reach even higher levels of sensitivity (~10E-29 e*cm). Since it is essential to perform EDM measurements on different targets in order to unfold the underlying physics, pEDM and dEDM searches are must-do experiments.
EDM experiments with charged particles are only possible at storage rings. In the ultimate experiment with a sensitivity beyond ~10E-29 e*cm, the EDM signal would be the vertical polarization produced by the EDM-induced precession of the frozen horizontal spin in a permanent radial electric field of a dedicated electric storage ring. The present proposal aims at a first direct measurement of the EDMs of protons and deuterons at ~10E-24 e*cm sensitivity level, and will be carried out in the conventional magnetic storage ring COSY of Forschungszentrum Jülich. Here the EDM signal would be the horizontal polarization produced by the EDM-induced precession of the frozen vertical spin in a radio-frequency electric flipper with horizontal electric field. Apart from providing the first direct access to pEDM and dEDM, literally all the outstanding technological and instrumental challenges for the proposed studies at COSY constitute groundbreaking work for the next generation of dedicated electric storage rings.
The research environment at Jülich coupled to the strong experienced groups of scientists and engineers from Jülich, RWTH-Aachen, Brookhaven National Laboratory, and Michigan State University, provides the ideal starting point, and constitutes, on a world-wide scale, the optimal basis for one of the most spectacular possibilities in modern science: finding a signal for new physics beyond the Standard Model through the detection of permanent electric dipole moments in a storage ring.