A fiber detector to monitor ortho-Ps formation and decay

Benjamin Rienäcker; Roberto Sennen Brusa; Ruggero Caravita; Sebastiano Mariazzi; Felix Pino; Oline Aas Ranum; Giancarlo Nebbia

doi:10.1016/j.nima.2021.166275

arXiv · 2111.01503

A fiber detector to monitor ortho-Ps formation and decay

Benjamin Rienäcker·Roberto Sennen Brusa·Ruggero Caravita·Sebastiano Mariazzi·Felix Pino·Oline Aas Ranum·Giancarlo Nebbia

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Abstract

We describe a novel method to use a scintillating fiber detector similar to the Fast Annihilation Cryogenic Tracking (FACT) used at the antimatter experiment AEgIS to monitor the presence of ortho-positronium. A single scintillating fiber was coupled to a photomultiplier tube and irradiated by flashes of about $6\cdot10^6$ $511\,\text{keV}$ $\gamma$-rays produced by $\approx10\,\text{ns}$ long positron pulses. The results were used to demonstrate the ability to track the creation and annihilation of ortho-positronium atoms over time in cryogenic and highly magnetic environments by using the FACT detector as a "digital calorimeter".

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Benjamin Rienäcker, Roberto Sennen Brusa, Ruggero Caravita, Sebastiano Mariazzi, Felix Pino, Oline Aas Ranum, Giancarlo Nebbia. 2021-11-02. A fiber detector to monitor ortho-Ps formation and decay. https://doi.org/10.1016/j.nima.2021.166275

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