Studying The Highest Energy Radiation Of The Crab Nebula

The origin of cosmic rays is one of the open questions in physics and astronomy.The observed energy spectrum of cosmic rays above Pe V energies indicates that there is Pe V particle accelerators(pevatrons)in the Galaxy,and discovery and identified new gamma-ray sources at ultra-high-energy(E_??100 Te V)play fundamental roles in the study of the origin of cosmic rays.Pulsar wind nebula(PWNe)are typical galactic Te V gamma ray sources.The Tibet-AS_?experiments have detected gamma-ray photons above100 Te V from Crab Nebula for the first time in 2019,opening the sub-Pe V astronomy window.Recently,the under-building LHAASO-KM2A has also detected gamma rays above 100 Te V form the Crab nebula,those observations provide valuable information for understanding the high energy physical process in the PWNe.In this paper,we study the high energy radiation from Crab nebula based on the model of Zhang et al.In this model,one of the high energy particles are accelerated in the magnetosphere,and the others are accelerated from the shock in the pulsar wind,and the spectra can be described by a broken power law with different indices and a break energy.The accelerated particles produce non-thermal photons via synchrotron radiation and inverse Compton scattering off soft photon fields.The observed spectra can be well explained by this model,and the predicted flux abve 100 Te V is 7.13×10^-11erg cm^-2s^-1.