Measurement of the Principal Quantum Number Distribution in a Beam of Antihydrogen Atoms

B. Kolbinger; C. Amsler; S. Arguedas Cuendis; H. Breuker; A. Capon; G. Costantini; P. Dupré; M. Fleck; A. Gligorova; H. Higaki; Y. Kanai; V. Kletzl; N. Kuroda; A. Lanz; M. Leali; V. Mäckel; C. Malbrunot; V. Mascagna; O. Massiczek; Y. Matsuda; D. J. Murtagh; Y. Nagata; A. Nanda; L. Nowak; B. Radics; C. Sauerzopf; M. C. Simon; M. Tajima; H. A. Torii; U. Uggerhøj; S. Ulmer; L. Venturelli; A. Weiser; M. Wiesinger; E. Widmann; T. Wolz; Y. Yamazaki; J. Zmeskal

arXiv · 2008.04246

Measurement of the Principal Quantum Number Distribution in a Beam of Antihydrogen Atoms

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Abstract

The ASACUSA (Atomic Spectroscopy And Collisions Using Slow Antiprotons) collaboration plans to measure the ground-state hyperfine splitting of antihydrogen in a beam at the CERN Antiproton Decelerator with initial relative precision of 10-6 or better, to test the fundamental CPT (combination of charge conjugation, parity transformation and time reversal) symmetry between matter and antimatter. This challenging goal requires a polarised antihydrogen beam with a sufficient number of antihydrogen atoms in the ground state. The first measurement of the quantum state distribution of antihydrogen atoms in a low magnetic field environment of a few mT is described. Furthermore, the data-driven machine learning analysis to identify antihydrogen events is discussed.

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B. Kolbinger, C. Amsler, S. Arguedas Cuendis, H. Breuker, A. Capon, G. Costantini, P. Dupré, M. Fleck, A. Gligorova, H. Higaki, Y. Kanai, V. Kletzl, N. Kuroda, A. Lanz, M. Leali, V. Mäckel, C. Malbrunot, V. Mascagna, O. Massiczek, Y. Matsuda, D. J. Murtagh, Y. Nagata, A. Nanda, L. Nowak, B. Radics, C. Sauerzopf, M. C. Simon, M. Tajima, H. A. Torii, U. Uggerhøj, S. Ulmer, L. Venturelli, A. Weiser, M. Wiesinger, E. Widmann, T. Wolz, Y. Yamazaki, J. Zmeskal. 2020-08-10. Measurement of the Principal Quantum Number Distribution in a Beam of Antihydrogen Atoms. https://arxiv.org/abs/2008.04246

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