Very high energy (VHE) gamma rays in pulsars, and their surrounding halos, are interpreted to originate from the leptonic channel and electromagnetic interactions through electron inverse Compton scattering. In the hadronic scenario, TeV-PeV gamma rays are generated from the decay of neutral pions, which are produced from cosmic ray (CR) protons interacting with the ambient medium. Recent observations of sub-PeV gamma rays from the halo of the pulsar PSR $\mathrm{J}0622+3749$ by the Large High Altitude Air Shower Observatory Kilometer-Square Array provide an opportunity to investigate the underlying emission mechanisms. Previous studies have shown that the observed emission can be consistently explained within a leptonic framework by the slow diffusion of electrons. In this work, we explore an alternative explanation based on the hadronic scenario through the proton-proton ($pp$) interaction channel, incorporating the observation of VHE gamma rays at 7 TeV by the high-altitude water Cherenkov detector. To model the observed gamma-ray spectrum, ranging from $\sim 7\mathrm{TeV}$ up to 200 TeV, the required CR proton luminosity is found to be ${\eta }_p\sim 0.14$ of the spin-down luminosity of PSR $\mathrm{J}0622+3749$. This scenario assumes that protons propagate in a one-zone superdiffusive environment, characterized by a diffusion index of $\alpha =1.05$, within an ambient density of $1{\mathrm{cm}}^{-3}$.

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• Cosmic ray & astroparticle detectors
• Particle astrophysics