Signatures of anisotropic diffusion around PeVatrons in 100 TeV gamma-ray data

Abstract

The Tibet AS$\gamma$ collaboration has reported a diffuse $\gamma$-ray emission signal from the Galactic Plane. We consider the possibility that the diffuse emission from the outer Galactic Plane at the highest energies is produced by cosmic rays spreading from a single supernova-type source either in the Local or Perseus arm of the Milky Way. We show that anisotropic diffusion of multi-PeV cosmic rays along the Galactic magnetic field can produce an extended source spanning ten(s) of degrees on the sky, with a flux-per-unit-solid-angle consistent with Tibet AS$\gamma$ measurements. Observations of this new type of very extended sources, and measurements of their morphologies, can be used to characterize the anisotropic diffusion of PeV cosmic rays in the Galactic magnetic field, and to constrain the locations and properties of past PeVatrons.

7 pages, 3 figures

References in corpus (5)

• Trigonometric Parallaxes Of High-Mass Star Forming Regions: Our View Of The Milky Way
• First Detection of sub-PeV Diffuse Gamma Rays from the Galactic Disk: Evidence for Ubiquitous Galactic Cosmic Rays beyond PeV Energies
• Energy spectra of secondaries in proton-proton interactions
• Escape model for Galactic cosmic rays and an early extragalactic transition
• Origin of Galactic sub-PeV diffuse gamma-ray emission: Constraints from high-energy neutrino observations