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arXiv · 0708.3717

Evidence For The Production Of Slow Antiprotonic Hydrogen 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. Macrì·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 present evidence showing how antiprotonic hydrogen, the quasistable antiproton-proton (pbar-p) bound system, has been synthesized following the interaction of antiprotons with the hydrogen molecular ion (H2+) in a nested Penning trap environment. From a careful analysis of the spatial distributions of antiproton annihilation events, evidence is presented for antiprotonic hydrogen production with sub-eV kinetic energies in states around n=70, and with low angular momenta. The slow antiprotonic hydrogen may be studied 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. Macrì, 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. 2007-08-28. Evidence For The Production Of Slow Antiprotonic Hydrogen In Vacuum. https://doi.org/10.1103/physrevlett.97.153401

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