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Why is the linac (linear accelerator)kept in a vacuum Watch

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    Please help!
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    (Original post by sarah99630)
    Please help!
    What do you mean the 'linac' is kept in a vacuum?

    Linac (Linear Accelerator) is a generic term often applied (but not exclusively) to the machine producing x-rays for radiotherapy medical procedures.

    The production of x-rays is accomplished within a vacuum for several reasons:

    One type of Linac produces x-rays by thermionic emission of electrons 'evaporated' from the surface of a suitable metal. The liberated electrons are accelerated by a strong magnetic field and these bombard a target which releases x-ray photon Bremsstrahlung radiation.

    The production and acceleration of electrons is performed in a vacuum to prevent oxidation and burn-out of the electrodes and target plate, which would otherwise soon be rendered inoperative.

    The vacuum is also needed to prevent electrons from colliding with gas atoms which would otherwise cause them to ionise the gas and force accelerated electrons to give up energy as unwanted heat and EM radiation therefore seriously reduces the efficiency and life of the machine.
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    (Original post by uberteknik)
    What do you mean the 'linac' is kept in a vacuum?

    Linac (Linear Accelerator) is a generic term often applied (but not exclusively) to the machine producing x-rays for radiotherapy medical procedures.

    The production of x-rays is accomplished within a vacuum for several reasons:

    One type of Linac produces x-rays by thermionic emission of electrons 'evaporated' from the surface of a suitable metal. The liberated electrons are accelerated by a strong magnetic field and these bombard a target which releases x-ray photon Bremsstrahlung radiation.

    The production and acceleration of electrons is performed in a vacuum to prevent oxidation and burn-out of the electrodes and target plate, which would otherwise soon be rendered inoperative.

    The vacuum is also needed to prevent electrons from colliding with gas atoms which would otherwise cause them to ionise the gas and force accelerated electrons to give up energy as unwanted heat and EM radiation therefore seriously reduces the efficiency and life of the machine.
    thank you sooo much for your help!!!
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