The Astrophysical Journal (Jan 2025)

Discovery of a Pulsar Wind Nebula Candidate Associated with the Galactic PeVatron 1LHAASO J0343+5254u

  • Stephen DiKerby,
  • Shuo Zhang,
  • Tülün Ergin,
  • Naomi Tsuji,
  • Kaya Mori,
  • Fabio Acero,
  • Samar Safi-Harb,
  • Shunya Takekawa,
  • Jooyun Woo

DOI
https://doi.org/10.3847/1538-4357/adb7e0
Journal volume & issue
Vol. 983, no. 1
p. 21

Abstract

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The astronomical origins of the most energetic galactic cosmic rays and gamma rays are still uncertain. X-ray follow-up of candidate “PeVatrons”—systems producing cosmic rays with energies exceeding 1 PeV—can constrain their spatial origin, identify likely counterparts, and test particle emission models. Using ∼120 ks of XMM-Newton observations, we report the discovery of a candidate pulsar wind nebula, a possible counterpart for the LHAASO PeVatron J0343+5254u. This extended source has a power-law X-ray spectrum with spectral index Γ _X = 1.9—softer at greater distance from the center—and asymmetric spatial extension out to $\approx 2^{\prime} $ . We conduct leptonic modeling of the X-ray and gamma-ray radiation from this complex system, showing that a fully leptonic model with elevated IR photon fields can explain the multiwavelength emission from this source, similar to other very high-energy pulsar wind nebulas; excess gamma-ray emissivity not explained by a leptonic model may be due to hadronic interactions in nearby molecular cloud regions, which might also produce detectable astroparticle flux.

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