Rabi Experiments on the $\sigma$ and $\pi$ Hyperfine Transitions in Hydrogen and Status of ASACUSA's Antihydrogen Program

Abstract

We report on the status of the in-beam hyperfine-structure measurements on ground-state antihydrogen by ASACUSA and on recent results obtained in supporting measurements from hydrogen. The $\sigma_1$ and $\pi_1$ transitions can now be investigated, which is beneficial from both theoretical and experimental perspectives. We discuss systematic effects from resonance interference originating from the chosen field geometries in the interaction region, and how their impact can be managed by appropriate data-taking or design concepts.