Detection of Very-High-Energy Gamma-Ray Emission from the Gamma-Ray Binary LS5039

Binary systems are potential very-high-energy (VHE) gamma-ray emitters, however, the VHE gamma-ray emission mechanism of these systems remains poorly understood. Recent observational results from H.E.S.S. and HAWC on the gamma-ray binary LS 5039 suggest that the binary system can efficiently accelerate particle, making it a possible candidate for the origin of PeV cosmic rays in the MilkyWay. In this study, we search for VHE gamma-rays above ∼10 TeV from the LS 5039, which consists of a massive star with a mass of 23 𝑀⊙ and an unknown compact object, using LHAASO data. Leveraging the high sensitivity of the LHAASO experiment in VHE gamma-ray observations, we have confirmed the VHE gamma-ray emission from LS 5039 up to 100 TeV, with its spectrum exhibiting no discernible cutoff.