A diffusive origin for the cosmic-ray spectral hardening reveals signatures of a nearbysource in the leptons and protons data

TL;DR

This paper proposes that spectral features in cosmic-ray data can be explained by a nearby hidden source combined with a diffusion coefficient that hardens at certain rigidities, aligning with recent experimental observations.

Contribution

It introduces a model linking cosmic-ray spectral features to a nearby source and a rigidity-dependent diffusion coefficient, consistent with multiple experimental datasets.

Findings

Spectral hardening at ~200 GV in diffusion coefficient is supported by light-nuclei data.

A nearby hidden source explains the spectral features at ~1 TeV and ~10 TeV.

Model aligns with anisotropy data and cosmic-ray observations.

Abstract

In this work we aim at reproducing, simultaneously, the spectral feature at $\sim 10 \, \mathrm{TeV}$ in the cosmic-ray proton spectrum, recently reported by the DAMPE Collaboration, together with the spectral break at $\sim 1 \, \mathrm{TeV}$ measured by H.E.S.S. in the lepton spectrum. Those features are interpreted as signatures of one nearby hidden cosmic-ray accelerator. We show that this interpretation is consistent with the dipole-anisotropy data as long as the rigidity scaling of the diffusion coefficient features a hardening at $\sim 200 \, \mathrm{GV}$, as suggested by the light-nuclei data measured with high accuracy by the AMS-02 Collaboration. Such rigidity-dependent diffusion coefficient is applied consistently to the large-scale diffuse cosmic-ray sea as well as to the particles injected by the nearby source.