Deceleration of a supersonic beam of SrF molecules to 120 m/s

We report on the deceleration of a beam of SrF molecules from 290 to 120~m/s. Following supersonic expansion, the molecules in the $X^2\Sigma$ ($v=0$, $N=1$) low-field seeking states are trapped by the moving potential wells of a traveling-wave Stark decelerator. With a deceleration strength of 9.6 km/s$^2$ we have demonstrated the removal of 85 % of the initial kinetic energy in a 4 meter long modular decelerator. The absolute amount of kinetic energy removed is a factor 1.5 higher compared to previous Stark deceleration experiments. The demonstrated decelerator provides a novel tool for the creation of highly collimated and slow beams of heavy diatomic molecules, which serve as a good starting point for high-precision tests of fundamental physics

Sensitive Search for an EDM on the Electron using BaF Molecules

The observation of an electron electric dipole moment (eEDM) larger than the value allowed by the Standard Model (SM) of particle physics would be direct evidence of new physics. An upper limit of the eEDM constrains extensions to the SM. The barium monofluoride molecule (BaF) is an excellent system for electron EDM searches. Its structure gives rise to a large effective electric field Eeff→ experienced by the valence electron, if the molecules are polarized by an external electric field. The particular structure of BaF enables their slowing down in a Stark decelerator [1] to velocities of several 10 m/s. With the addition of laser cooling a bright and slow molecular beam can be created. The components of the experiment, from the cryogenic source of BaF to the magnetically shielded interaction zone will be discussed and the experimental strategy will be explained. The goal of the project is a statistical limit of 5 · 10−30 e cm. At the projected precision the results of this experiment complement results in high energy physics experiments, e.g. at LHC. [1] J.E. van den Berg, et al., J. Mol. Spec. 300, 22 (2014

Sensitive Search for an EDM on the Electron using BaF Molecules

The observation of an electron electric dipole moment (eEDM) larger than the value allowed by the Standard Model (SM) of particle physics would be direct evidence of new physics. An upper limit of the eEDM constrains extensions to the SM. The barium monofluoride molecule (BaF) is an excellent system for electron EDM searches. Its structure gives rise to a large effective electric field Eeff→ experienced by the valence electron, if the molecules are polarized by an external electric field. The particular structure of BaF enables their slowing down in a Stark decelerator [1] to velocities of several 10 m/s. With the addition of laser cooling a bright and slow molecular beam can be created. The components of the experiment, from the cryogenic source of BaF to the magnetically shielded interaction zone will be discussed and the experimental strategy will be explained. The goal of the project is a statistical limit of 5 · 10−30 e cm. At the projected precision the results of this experiment complement results in high energy physics experiments, e.g. at LHC. [1] J.E. van den Berg, et al., J. Mol. Spec. 300, 22 (2014