Fundamental Experiments with Positronium Confined in Micro-Cavities and Emitted into Vacuum with the New Bunched Positron Beam at the Antimatter Lab of Trento

Abstract:

A new bunched positron (e⁺) beam is currently under final development at the AntiMatter Laboratory (AML) of the University of Trento. The positron beam has been designed to deliver bunches containing up to a few 10⁵ positrons compressed to durations of less than 2 ns and with a tunable energy range between 1 and 21 keV. Thanks to the specifications of this new apparatus, different experiments based on the production of positronium (Ps) in nanostructured e⁺/Ps converters have been planned. A silicon target with nanochannels connected to laser-written buried micro-cavities is under development. The intent is to produce Ps atoms in the nanochannels and collect them in the micro-cavities to explore the mechanisms of Ps/cavity walls interaction and Ps/Ps interaction. Moreover, Ps clouds emitted into vacuum after implantation of e⁺ bunches in nanochanneled e⁺/Ps converters will be employed to perform measurements of the entanglement of the three annihilation gamma-rays of Ps and the inertial sensing on Ps. In this work, the characteristics of the new positron beam at the AML of Trento will be presented and the scheduled experiments will be illustrated.

• Periodical: Solid State Phenomena (Volume 374)
• Pages: 13-21
• DOI: https://doi.org/10.4028/p-uDRz4Y
• Online since: July 2025
• Authors: Sebastiano Mariazzi*, Ahmad Chehaimi, Luca Penasa, Ruggero Caravita, Roberto Sennen Brusa
• Keywords: Micro-Cavities, Nanochannels, Positron Beam, Positronium

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