Introduction

Astrophysical accelerators of cosmic rays (CRs) with energies higher than \(1\, \textrm{PeV}\) ( \(= 10^{15}\, \textrm{eV}\) ), the so-called PeVatrons, are not identified yet. To identify PeVatrons, the observation of sub-PeV gamma rays ( \(E > 100\, \textrm{TeV}\) ) from astrophysical sources is important. As of today, observatories such as Tibet AS \(\gamma \) experiment, HAWC, LHAASO, and H.E.S.S. have detected several sub-PeV gamma-ray sources, but the robust identification of PeVatrons are still to be established due to the lack of detail studies of the individual sources. This work observes two gamma-ray sources HESS J1843 \(-033\) and HESS J1849−000 in the sub-PeV energy range and discusses the potential PeVatron nature of these sources.