Mr Michał Rawlik (ETH Zürich)Mr Nicholas Ayres (University of Sussex)
The strong CP problem may be solved by turning the theta parameter into a dynamic field. Excitations of this field are axions, which are also good cold dark matter candidates. The nEDM experiments are sensitive to interactions with a background field of ultralight axions, which would appear as oscillations in the measured neutron electric dipole moment. This analysis presents the first laboratory constraints on the axion-gluon coupling. Sensitive for periods from minutes to decades, we probe over 8 orders of magnitude in mass.
Collaboration nEDM (at PSI)