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X-Ray Source

  1. Aug 24, 2010 #1
    Why do accelerating electrons (synchrotron) emit x-rays, but accelerating protons (cyclotron) don't? Both are accelerating/decelerating charges.
  2. jcsd
  3. Aug 24, 2010 #2
    The emission power of synchrotron radiation depends on the relativistic Lorentz factor γ to the fourth power, so 10 GeV electrons radiate much more than 10 GeV protons, other factors being the same. See


    Protons do radiate synchrotron radiation. It is expected to be a serious problem in LHC at full energy (7 GeV per beam), because the proton synchrotron radiation is soft x-rays, that cause residual gas atoms adsorbed to the beam tube walls to desorb, causing a vacuum pressure rise and proton residual gas scattering and beam loss.

    Bob S
  4. Aug 24, 2010 #3
  5. Aug 26, 2010 #4
    Thanks to both for the reference, it's a great help.
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