#X-ray_tube  a vacuum tube containing a metal target onto which a beam of electrons is directed at high energy for the generation of X rays
  supertype:  thermionic_vacuum_tube__tube__vacuum_tube__thermionic_tube__electron_tube__thermionic_valve  electronic device consisting of a system of electrodes arranged in an evacuated glass or metal envelope
  part of:  X-ray_machine  an apparatus that provides a source of X rays

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