Thursday, December 6, 2018, 16:00
WHGA Auditorium
Frank Rathmann, Forschungszentrum Jülich
Abstract:
The Standard Model (SM) of Particle Physics is not capable to account for the
apparent matter-antimatter asymmetry of our Universe. Physics beyond the SM is
required and is either probed by employing highest energies (e.g. at LHC), or by
striving for ultimate precision and sensitivity (e.g. in the search for electric dipole
moments). Permanent electric dipole moments (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.
Up to now, EDM searches focused on neutral systems (neutrons, atoms, and
molecules). Storage rings, however, offer the possibility to measure EDMs of charged
particles by observing the influence of the EDM on the spin motion in the ring [1, 2, 3].
Direct searches of proton and deuteron EDMs bear the potential to reach sensitivities
beyond 10^(-29) e cm. Since the Cooler Synchrotron COSY at the Forschungszentrum
Jülich provides polarized protons and deuterons up to momenta of 3.7 GeV/c, it
constitutes an ideal testing ground and starting point for such an experimental programme.
The talk will present the JEDI plans for the measurement of charged hadron EDMs
and discuss recent results.
[1] D. Eversmann et al., Phys. Rev. Lett. 115, 094801 (2015)
[2] A. Saleev et al., Phys. Rev. Accel. Beams 20, 072801 (2017)
[3] N. Hempelmann et al., Phys. Rev. Accel. Beams 21, 042002 (2018)