Emission of Electromagnetic Radiation Bremsstrahlung

For two particles traveling in the same medium, the lighter particle will emit a much greater amount of bremsstrahlung than the heavier particle (other things being equal). 

More bremsstrahlung is emitted if a particle travels in a medium with high atomic number Z than in one with low atomic number. 

For charged particles with energies considered here, the kinetic energy lost as bremsstrahlung might be important for electrons only. Even for electrons, it is important for high-Z materials like lead (Z = 82). For more detailed treatment of the emission of bremsstrahlung, the reader should consult the references listed at the end of the chapter. 

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