Antiprotons and Elementary Particles over a Solar Cycle: Results from the Alpha Magnetic Spectrometer

Editors' Suggestion Featured in Physics Physics Viewpoint
Phys. Rev. Lett. 134, 051002 (2025)
Published on:
Abstract

We present results over an 11-year solar cycle of cosmic antiprotons based on $1.1 \times 10^6$ events in the rigidity range from 1.00 to 41.9 GV. The $\overline{p}$ fluxes exhibit distinct properties. The magnitude of the $\overline{p}$ flux temporal variation is significantly smaller than those of $p$, $e^-$, and $e^+$. A hysteresis between the $\overline{p}$ fluxes and the $p$ fluxes is observed whereas the $\overline{p}$ and $e^-$ fluxes show a linear correlation. With a model-independent analysis, we found a  universal relation between the shape of the rigidity spectrum and the magnitude of flux temporal variation over an 11-year solar cycle for both positively and negatively charged particles. The simultaneous results on $\overline{p}$ and $p$, $e^-$, $e^+$, provide unique information for understanding particle transport in the solar system as a function of mass, charge, and spectral shape.

Download AMS Data

Antiproton fluxes for each Bartels rotation

11-year time-averaged antiproton flux

Extra tables:

Average electron fluxes
Average positron fluxes
Proton fluxes for each Bartels rotation
Average proton fluxes
Electron fluxes for each Bartels rotation
Positron fluxes for each Bartels rotation

External Databases
AMS Data at CRDB (Cosmic-ray DataBase)

The CRDB at LPSC/IN2P3/CNRS, online since 2013, is fully described in Maurin et al. (2014, 2020)

AMS Data at Cosmic Ray DataBase (CRDB) © SSDC

The CRDB © SSDC is developed at the Space Science Data Center, a facility of the Italian Space Agency (ASI).