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arXiv · 2607.04197

The Amerigo Vespucci as a traveling laboratory for studying the cosmic-ray fluxes at sea level

Davide Cerasole·Federica Cuna·Gaia De Palma·Riccardo Di Tria·Leonardo Di Venere·Fabio Gargano·Mario Giliberti·Francesco Licciulli·Antonio Liguori·Pierpaolo Loizzo·Francesco Loparco·Leonarda Lorusso·Mario Nicola Mazziotta·Giuliana Panzarini·Roberta Pillera·Davide Serini
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Abstract

We have installed and operated a plastic scintillator detector counter to measure the flux of cosmic radiation during the 2023-2025 tour of the historical vessel Amerigo Vespucci. The Vespucci is the oldest ship of the Italian Navy and serves as a training vessel for Navy cadets. During its tour, some experiments were hosted onboard the vessel, providing unique opportunities for scientists working in different fields. We installed our detector upon the Vespucci's departure from Darwin in early October 2024. The detector collected cosmic-ray data during the journey from Darwin to Trieste, where the worldwide tour ended in March 2025. After about one month of stop in Trieste, the ship continued its tour in the Mediterranean sea, and arrived in Genova on June 10, 2025. We performed measurements of the cosmic radiation reaching the sea level across a wide latitude range, from 15° S to about 45° N. The lowest rate (averaged over all azimuth angles) was measured at a geographic latitude of about 7° N, and was about 16% less than the highest value, which was measured at Trieste, the northernmost location of the journey. Latitude effects on the cosmic radiation flux at sea level are due to the quasi-dipole geomagnetic field configuration, tilted by an angle of about 11° with respect to Earth's rotational axis.

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Davide Cerasole, Federica Cuna, Gaia De Palma, Riccardo Di Tria, Leonardo Di Venere, Fabio Gargano, Mario Giliberti, Francesco Licciulli, Antonio Liguori, Pierpaolo Loizzo, Francesco Loparco, Leonarda Lorusso, Mario Nicola Mazziotta, Giuliana Panzarini, Roberta Pillera, Davide Serini. 2026-07-05. The Amerigo Vespucci as a traveling laboratory for studying the cosmic-ray fluxes at sea level. https://doi.org/10.1038/s41598-025-24181-7

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