Harold E Johns

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Across
  1. 1. Dr. Johns' book was titled the physics of __
  2. 5. University where he created the Cobalt-60 radiation unit
Down
  1. 2. Devices that uses x-ray beams to accelerate charged particle in a straight line
  2. 3. Isotope used in the first targeted cancer radiation therapy
  3. 4. Where Dr. Johns was born