Speaker
Description
Understanding the origins of the cosmos has been a much sought after pursuit. One of the greatest mysteries is the composition of the universe itself, which deviates from the Standard Model predictions, since observations indicate that it is made almost entirely out of matter [1]. These observations paved the way for experiments that directly compare matter and antimatter, with the latest one being on the effect of gravity on antimatter [2].
A novel scheme for producing cold, magnetically trappable atomic hydrogen has been proposed [3]. The whole process relies on the production of Ba+/BaH+ ions through laser ablation of a solid BaH2 target, trapping these ions, laser cooling Ba+ and thus sympathetically cooling BaH+ ions, and finally photodissociating BaH+ ions to produce atomic hydrogen. We designed a new experimental setup, with a Paul trap as the main feature, as a proof of concept of the proposed scheme.
Here, I present our first results on the trapping and laser cooling of Ba+ ions extracted from a Ba target, as well as removing BaO, that was formed during handling the target, from its surface. Next phase of the experiment will use a BaH2 target and will result in the production of hydrogen. These techniques are compatible with the current generation antihydrogen experiments [4], since they all use ion traps to form antihydrogen, and make the whole scheme suitable for loading hydrogen into an antihydrogen experiment, for the direct comparison of the two species.
[1] G. Steigman. Observational tests of antimatter cosmologies. Annual review of astronomy and astrophysics 14 (1), 339 – 372 (1976).
[2] E. K. Anderson, C. J. Baker, W. Bertsche, et al. Observation of the effect of gravity on the motion of antimatter. Nature 621, 716–722 (2023).
[3] S. A. Jones. An ion trap source of cold atomic hydrogen via photodissociation of the BaH+ molecular ion. New J. Phys. 24, 023016 (2022).
[4] G. Andresen, M. Ashkezari, M. Baquero-Ruiz, et al. Trapped antihydrogen. Nature 468, 673–676 (2010).
