The Study Of Emission From Pulsar TeV Halos

TeV halo is one kind of newly discovered extended TeV gamma ray sources around the middle-aged gamma rays pulsars,and the scale is about several ten pc.The studies showed that the gamma rays from TeV halo are produced by the inverse Compton scattering of relativistic electrons escaping form pulsar wind nebula with soft photons.However,how electron diffuse to such a large distance is still unknown,which challenge the traditional particle diffusion model.There are three confirmed TeV halos,two of which were discovered by HAWC detector and one by Large High Altitude Air Shower Observatory(LHAASO).With the further observation of LHAASO,more TeV halos will be detected,which can help us to understand the physics of TeV halo.In the thesis,we mainly study the high-energy physical process of TeV halo.In the Chapter 2,we introduce the basic knowledge of pulsars,pulsar wind nebulae and TeV halos.In the Chapter 3,the observational characteristics of TeV halo and the high-energy radiation model are introduced in detail,including the particle diffusion process,influence of different injection electron spectrum on the energy spectrum.And we further introduce the one-zone and two-zone models to explain TeV halo.In the Chapter 4,we apply the models to seven sources,including three identified TeV halos,i.e.,LHAASO J0621+3755 that around PSR J0622+3749,the TeV halo of Geminga and Monogem.Two sources,HWAC J0635+070 and HAWC J0543+233,are detected near PSR J0633+0632 and PSR B0540+23,which are reported as possible TeV halo.The expansion sources 2HWC J1831-0981 and 2HWC J0231+415 around PSR J1831+0952 and PSR J2032+4127 have high probability of being TeV halo.The main results are as follows.(1)We use one-zone slow diffusion model and two-zone diffusion model to fit the radiation spectrum of LHAASO J0621+3755,Geminga and Monogem’s TeV halo.The observed results can be will reproduced,and we obtained the model parameters,and compare the differences between the two models.(2)the radiation energy spectrum of the remaining four sources is predicted and compared with the LHHASO sensitivity,which can be observed by LHAASO observation.