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X-Rays: Energy Deposition in a Nutshell
X rays do 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 (2 Gy) requires
~10
8-9
incident x rays per
mm
2
.