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arXiv · 0801.3193

Production of Slow Protonium in Vacuum

N. Zurlo·M. Amoretti·C. Amsler·G. Bonomi·C. Carraro·C. L. Cesar·M. Charlton·M. Doser·A. Fontana·R. Funakoshi·P. Genova·R. S. Hayano·L. V. Jorgensen·A. Kellerbauer·V. Lagomarsino·R. Landua·E. Lodi Rizzini·M. Macri'·N. Madsen·G. Manuzio·D. Mitchard·P. Montagna·L. G. Posada·H. Pruys·C. Regenfus·A. Rotondi·G. Testera·D. P. Van der Werf·A. Variola·L. Venturelli·Y. Yamazaki
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Abstract

We describe how protonium, the quasi-stable antiproton-proton bound system, has been synthesized following the interaction of antiprotons with the molecular ion H$_2^+$ in a nested Penning trap environment. From a careful analysis of the spatial distributions of antiproton annihilation events in the ATHENA experiment, evidence is presented for protonium production with sub-eV kinetic energies in states around $n$ = 70, with low angular momenta. This work provides a new 2-body system for study using laser spectroscopic techniques.

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N. Zurlo, M. Amoretti, C. Amsler, G. Bonomi, C. Carraro, C. L. Cesar, M. Charlton, M. Doser, A. Fontana, R. Funakoshi, P. Genova, R. S. Hayano, L. V. Jorgensen, A. Kellerbauer, V. Lagomarsino, R. Landua, E. Lodi Rizzini, M. Macri', N. Madsen, G. Manuzio, D. Mitchard, P. Montagna, L. G. Posada, H. Pruys, C. Regenfus, A. Rotondi, G. Testera, D. P. Van der Werf, A. Variola, L. Venturelli, Y. Yamazaki. 2008-01-21. Production of Slow Protonium in Vacuum. https://doi.org/10.1007/s10751-007-9529-0

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