Diffuse Ultra-High-Energy Gamma-Ray Emission From TeV Halos

Abstract

The LHAASO Collaboration has recently reported a measurement of the diffuse gamma-ray emission from the Galactic Plane at energies between 10 TeV and 1 PeV. While this emission is brighter than that expected from cosmic-ray interactions in the interstellar medium alone, we show that the intensity, spectrum, and morphology of this excess are in good agreement with that predicted from the "TeV halos" which surround the Milky Way's pulsar population. These results support the conclusion that TeV halos dominate the ultra-high-energy sky, and that these objects convert $\sim 5\%$ of their total spindown power into very-high and ultra-high-energy photons.

7 pages, 3 figures, 1 appendix, v2: version published in PRD

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Cited by in corpus (10)

• Measurement of Very-high-energy Diffuse Gamma-ray Emissions from the Galactic Plane with LHAASO-WCDA
• On the Contribution of Unresolved Pulsars to the Ultra-high-energy Galactic Diffuse Gamma-Ray Emission
• Energy dependence of the knee in the cosmic ray spectrum across the Milky Way
• Imprints of PeV cosmic-ray sources on the diffuse gamma-ray emission
• A New Perspective on the Diffuse Gamma-Ray Emission Excess
• Absence of TeV halos around millisecond pulsars
• Extended TeV Halos May Commonly Exist around Middle-Aged Pulsars
• PHECT: A lightweight computation tool for pulsar halo emission
• Search for TeV emission from spider millisecond pulsars with HAWC
• Interpreting the LHAASO Galactic diffuse emission data