Pulsed production of antihydrogen and other antiprotonic systems for precisions tests of fundamental symmetries

• Michael Doser (CERN)

The production of cold antihydrogen atoms at CERN's Antiproton Decelerator (AD) has opened up the possibility to perform direct measurements of the Earth's gravitational acceleration on antimatter bodies. This is the main goal of the AEgIS collaboration: to measure the value of g using a pulsed source of cold horizontally travelling antihydrogen via a moiré deflectometer/Talbot-Lau interferometer. The first milestone of pulsed production of antihydrogen [1] using a resonant charge-exchange reaction between cold trapped antiprotons and Rydberg positronium (or Ps, the atomic bound state of a positron and an electron) atoms, and the techniques it relies on, will be presented. The outlook in enhancing the intensity of the pulsed antihydrogen source thanks to the 100 keV ELENA decelerator antiproton beam will be discussed, with a view to the first gravitational experiments using a pulsed beam of antihydrogen in the near future. Further physics directions in AEgIS relying on similar pulsed interactions in positronium or between antiprotons and Rydberg atoms and molecules will also be touched upon, as they open up unexplored venues in nuclear physics and novel precision tests of fundamental symmetries. [1] C. Amsler et al. (The AEgIS collaboration), Pulsed production of antihydrogen, Commun. Phys. 4, 19 (2021) https://doi.org/10.1038/s42005-020-00494-z