In the period spanning the first scientific period we focused on implementing necessary upgrades in an apparatus which was previously developed and employed for preliminary parity violation (PV) measurements. The key goal of this set of activities was to obtain enough experimental sensitivity, so that the planned highly precise PV measurements can be undertaken. As a result of the work, we achieved a nearly two-orders-of magnitude improvement, relative to the original apparatus sensitivity. That is, the same accuracy in the measurements of the PV effect in our preliminary experiments, can be now obtained with nearly two-orders-of-magnitude smaller measurement time.
Another major activity we undertook involved detailed studies of systematic effects that are expected to affect our forthcoming PV measurements. These studies are separate for Yb isotopes with zero nuclear spin, and spinful isotopes. For the former case, systematic effects are now well understood, and this opens the way to proceed with our planned isotopic comparison measurements. (At the same time, systematics in the spinful isotopes are still being investigated.)
Early in the project we used part of the setup for a project related to our main ERC project goal: a check for new particles, beyond those included in the Standard Model of particle physics. A previous work had hinted at new particles, and that motivated us to do a complementary check using our Yb apparatus for laser spectroscopy, to validate this possibility. Our results largely diminished the scenario for new particles.
