Probing the Standard Model of Particle Physics with Ultracold Neutrons
Dieter Ries (University of Mainz)

Ultracold Neutrons (UCN) provide a unique tool for fundamental neutron research with long observation times. Once produced e.g. in one of the UCN sources at the TRIGA Mainz research reactor, they can be confined by suitable materials, gravity or strong magnetic fields ultimately only limited by the beta decay lifetime of the free neutron.
The τSPECT experiment, which is close to being fully commissioned on-site at JGU, aims for a precision determination of the neutron lifetime, which is currently under scrutiny because different measurement techniques yield incompatible results.
Another precision measurement with UCN is the search for a non-vanishing electric dipole moment of the neutron, which would violate CP symmetry.
Together with the international nEDM collaboration we have recently published a new upper limit on the neutron EDM and are currently commissioning the next generation experiment "n2EDM" at PSI, Switzerland, which aims to push down the limit by an order of magnitude in the coming years. The current state of and results from the τSPECT, nEDM and n2EDM experiment will be presented.