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arXiv · 2610.27635

Probing Nearby Electron Sources and Local Diffusion with the TeV All-Electron Spectrum

Zhen Xie·Ruizhi Yang
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Abstract

Radiative losses restrict multi-TeV cosmic-ray electrons to young nearby accelerators, allowing the all-electron spectrum (electrons plus positrons) to retain information about particle release and local transport. We investigate how a nearby source can shape this spectrum using Vela as a representative example. We compare a birth-time burst with continuous release for the same total injected electron energy and examine the dependence on the diffusion coefficient, injection index, and source energetics. The burst spectrum develops a cooling-limited boundary near 28 TeV at the age of Vela, whereas continuous release produces a broader high-energy tail through the contribution of recently injected particles. The flux at Earth is largest over a finite range of diffusion coefficients, reflecting the competition between inefficient arrival and spatial dilution. Harder injection spectra and larger released energies increase the source contribution in the multi-TeV region, and we map the combinations of injection index and released electron energy that can produce an observable spectral feature. For anisotropic diffusion, the source visibility also depends on the angle between the Vela-Earth direction and the local ordered magnetic field. Future direct measurements extending the all-electron spectrum beyond several TeV could therefore distinguish different release histories and constrain both the energetics of nearby sources and local cosmic-ray transport.

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Zhen Xie, Ruizhi Yang. 2026-10-20. Probing Nearby Electron Sources and Local Diffusion with the TeV All-Electron Spectrum. https://arxiv.org/abs/2610.27635

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