Abstract

The discrete symmetries Parity (P), Time-reversal (T) and Charge conjugation (C) play a central role in the Standard Model (SM) of the electro-weak interactions. In 1957 it was discovered that P is maximally violated in the weak interaction. A few years later, a small violation of the combined symmetry CP was discovered. CP violation is thought to be a source for the matter-antimatter asymmetry in the universe. Is there more symmetry violation in nature? At KVI, we are probing discrete symmetries in several experiments with rare isotopes, which are produced at the TRImP facility. In particular, we are searching for a nonzero value of the permanent electric dipole moments (EDMs) of the heavy alkaline earth metal radium, which would violate P and T at the same time. Short lived radium isotopes are expected to be uniquely sensitive to EDMs due to their nuclear and atomic structure. An experimental search for an EDM is possible due to the combination of nuclear physics for the production of the isotopes and the high precision atomic physics methods. Within the experimental program we extended laser cooling techniques to the alkaline earth element barium which we trapped for the first time and we started a program on precision laser spectroscopy.