Studies of Exotic Physics with Antiprotons and Protons (Prof. Stefan Ulmer)
- Date: Jan 31, 2023
- Time: 02:30 PM (Local Time Germany)
- Speaker: Prof. Stefan Ulmer
- Heinrich Heine Universitaet Duesseldorf & RIKEN, Fundamental Symmetries Laboratory, Wako, Saitama, Japan
- Location: Max Planck Institute of Quantum Optics
- Room: Herbert Walther Lecture Hall
Using advanced cryogenic Penning traps, we have recently performed the most precise measurement of the proton-to-antiproton charge-to-mass ratio with a fractional uncertainty of 16 parts in a trillion . In another measurement, we have invented a novel spectroscopy method, that allowed for the first direct measurement of the antiproton magnetic moment with a fractional precision of 1.5 parts in a billion . Together with our last measurement of the proton magnetic moment  this improves the precision of previous magnetic moment based tests of the fundamental CPT invariance by more than a factor of 3000. A time series analysis of the sampled magnetic moment resonance furthermore enabled us to set first direct constraints on the interaction of antiprotons with axion-like particles (ALPs) , and most recently, we have used our ultra-sensitive single particle detection systems to derive constraints on the conversion of ALPs into photons . In parallel we are working on the implementation of new measurement technology to sympathetically cool antiprotons  and to apply quantum logic inspired spectroscopy techniques . I will review the recent results produced by BASE, with particular focus on the recent 16 p.p.t. comparison of the antiproton-to-proton charge-to-mass ratio. I will also outline strategies to further improve our high-precision studies of matter-antimatter symmetry, which will include the implementation of the transportable antiproton trap BASE-STEP.
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