Precision measurement of antiproton to proton ratio with the Alpha Magnetic Spectrometer on the International Space Station

Francesco Nozzoli

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arXiv · 1701.00086

Precision measurement of antiproton to proton ratio with the Alpha Magnetic Spectrometer on the International Space Station

Francesco Nozzoli

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Abstract

A precision measurement by AMS of the antiproton-to-proton flux ratio in primary cosmic rays in the absolute rigidity range from 1 to 450 GV is presented based on $3.49\times10^5$ antiproton events and $2.42\times10^9$ proton events. Above $\sim60$ GV the antiproton to proton flux ratio is consistent with being rigidity independent. A decreasing behaviour is expected for this ratio considering the traditional models for the secondary antiproton flux.

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Francesco Nozzoli. 2016-12-31. Precision measurement of antiproton to proton ratio with the Alpha Magnetic Spectrometer on the International Space Station. https://arxiv.org/abs/1701.00086

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