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arXiv · 2502.19244

Deciphering the Electron Spectral Hardening in AMS-02

Carmelo Evoli
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Abstract

We analyze the electron cosmic-ray spectrum from AMS-02, focusing on the spectral hardening around 42 GeV. Our findings confirm that this feature is intrinsic to the primary electron component rather than a byproduct of contamination from primary positron sources. Even under conservative assumptions, its significance remains at about $7\sigma$, strongly indicating a genuine spectral break. Accordingly, we introduce a new, more realistic parametric fit, which we recommend for the next round of AMS-02 analyses. Once the sources of systematic uncertainties are better constrained, this refined approach can either reinforce or refute our conclusions, providing a clearer understanding of the observed electron spectrum. If confirmed, we propose that this hardening most likely arises from interstellar transport or acceleration effects.

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Carmelo Evoli. 2025-02-26. Deciphering the Electron Spectral Hardening in AMS-02. https://doi.org/10.3390/astronomy4010004

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