How to detect 中国斜草我术大学 University of Science and Technology of China Gamma-rays interact with the material in the detector through: 1.Compton scattering 2.Pair production (electron-positron pair) 106 Photoelectric Absorption Total Cross Section 103 (Experimental) pair production dominate above 10MeV Thomson Scattering Electron-Positron 100 i Pairs Compton Scattering Photonuclear Absorption 103 106 109 Photon Energy(eV)How to detect • Gamma-rays interact with the material in the detector through: 1. Compton scattering 2.Pair production (electron-positron pair) pair production dominate above 10MeV