High-Statistics Measurement of the Cosmic-Ray Electron Spectrum with H.E.S.S

2024/11/12 by F. Aharonian, F. Ait Benkhali, J. Aschersleben +144 · 1 voice
Physics and Astronomy · #astro-ph.HE

paper · pdf · doi:10.1103/physrevlett.133.221001

Abstract

Owing to their rapid cooling rate and hence loss-limited propagation distance, cosmic-ray electrons and positrons (CRe) at very high energies probe local cosmic-ray accelerators and provide constraints on exotic production mechanisms such as annihilation of dark matter particles. We present a high-statistics measurement of the spectrum of CRe candidate events from 0.3 to 40 TeV with the High Energy Stereoscopic System (H.E.S.S.), covering two orders of magnitude in energy and reaching a proton rejection power of better than 10⁴. The measured spectrum is well described by a broken power law, with a break around 1 TeV, where the spectral index increases from Γ₁ = 3.25 ± 0.02 (stat) ± 0.2 (sys) to Γ₂ = 4.49 ± 0.04 (stat) ± 0.2 (sys). Apart from the break, the spectrum is featureless. The absence of distinct signatures at multi-TeV energies imposes constraints on the presence of nearby CRe accelerators and the local CRe propagation mechanisms.

Discussions

• High-Statistics Measurement of the Cosmic-Ray Electron Spectrum with H.E.S.S.: arxiv.org/abs/2411.08189 -> Measuring the Spectrum of High-Energy Cosmic-Ray Electrons: physics.aps.org/articles/v17... [bsky, 0 points, 0 comments]

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