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

TL;DR

This study reports the discovery of a candidate pulsar wind nebula associated with a galactic PeVatron, using X-ray observations to explore its properties and potential role in cosmic ray acceleration.

Contribution

It presents the first identification of a pulsar wind nebula candidate linked to a PeVatron, with detailed X-ray spectral and spatial analysis and leptonic modeling of its emission.

Findings

Discovered a candidate pulsar wind nebula with asymmetric X-ray extension.

Leptonic models can explain the multiwavelength emission with elevated IR fields.

Possible hadronic interactions in nearby clouds may contribute to gamma-ray excess.

Abstract

The astronomical origin of the most energetic galactic cosmic rays and gamma rays is still uncertain. X-ray followup 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 of 1.9 - softer at greater distance from the center - and asymmetric spatial extension out to 2'. 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 VHE pulsar wind nebulae; 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.