Speaker
Description
In the LEMING experiment we aspire to carry out next generation laser spectroscopy and gravity experiments using a novel cold atomic beam of muonium (Mu = μ⁺ + e⁻). The result of a Mu free fall measurement would reveal a clean coupling of gravity to elementary (anti)leptons from the second generation, complementary to all existing probes - normal atoms and recently antihydrogen - where composite hadronic masses dominate the interaction.
To measure the expected nanometer-scaled displacements of Mu trajectories by gravitational acceleration, phase-sensitive methods like atom interferometry is needed. However, state-of-the-art thermal muonium sources were not amenable to produce the contrast and intensity needed for such a measurement.
We recently succeeded in developing a novel cold atomic Mu beam in vacuum using muon conversion in a thin layer of superfluid helium (SFHe), amenable to atom interferometry. Muonium atoms were synthesized and thermalized to below v_t ~ 0.06 km/s velocities in SFHe, and gained v ~ 2.2 km/s velocity at the surface in normal direction by transforming the chemical potential to kinetic energy. We report here the synthesis of this high luminosity beam, resulting in ~10% conversion efficiency of the stopped muons to vacuum muonium. Latest results concerning the atomic interferometer setup and the feasibility studies of the various precision experiments will be also presented.
