WIDG Seminar: Maximilian Beyer, Yale, “Measuring nuclear-spin-dependent parity violation with molecules”

Nuclear-spin-dependent parity violation (NSD-PV) effects in atoms and molecules arise from Z0 boson exchange between electrons and the nucleus and from the magnetic interaction between electrons and the parity-violating nuclear anapole moment.
NSD-PV level mixing is observed using a Stark interference technique in combination with Zeeman shifting different rotational states of the molecule to near degeneracy using a magnetic field. This near-degeneracy enhances the mixing of opposite-parity states due to NSD-PV and leads to much larger PV signals than can be obtained in similar experiments in atoms.
Recently, unprecedented sensitivity to NSD-PV effects was demonstrated, using the most abundant isotopologue 138-BaF. The zero nuclear spin for 138-Ba and the negligible NSD-PV due to the 19-F nucleus allowed the characterization of the inherent systematic uncertainties of the measurement scheme.
Ongoing work will be presented to measure NSD-PV in 137-BaF and 135-BaF. A cryogenic buffer-gas beam source was installed for producing a cold and slow molecular beam of 138-BaF, 137-BaF and 135-BaF.
Host: Ako Jamil