Energy Loss Due to Bremsstrahlung Emission

The calculation of energy loss due to emission of bremsstrahlung is more involved than the calculation of energy loss due to ionization and excitation. Here, an approximate equation will be given for electrons or positrons only, because it is for these particles that energy loss due to emission of radiation may be important. 

For electrons or positrons with kinetic energy T (MeV) moving in a material with atomic number Z, the energy loss due to bremsstrahlung emission, (dE/dx)j, is given in terms of the ionization and excitation energy loss by Eq. 

Example 43 Consider an electron with T = 5 MeV. What fraction of its energy is lost as bremsstrahlung as it starts moving (a) in aluminum and (b) in lead  

That is, the rate of energy loss due to radiation is about 9 percent of dE/dx). (b) For the same electron moving in lead (Z = 82), 

In this case, the rate of radiation energy loss is 55 percent of idE/dx).  

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