ATP Barcelona 2017

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X-Rays: Energy Deposition in a Nutshell
 X rays are ionize indirectly.
 On interaction, energy is
scattered or transferred to
electrons, then absorbed.
 Biological effect depends on the
amount of energy absorbed
( dose).
 Tracking electrons is highly
important for accurate dose
calculations.
 One treatment (2Gy) requires
~108-9 incident x rays per mm 2.