**3.4 Dosimetry**

The rate at which materials absorb radiation is also critical in a high-radiation environment. As a result, ion beam technology is commonly used to examine how these nuclear materials absorb various types of radiation. The designer will then know where to put which material. Each component of the nuclear reactor system and its function; some absorb, some reflect, some moderate fast neutrons, while others prevent leakage. A material may qualify for leakage protection yet not be suitable for absorbing neutrons in the form of a control rod and vice versa.

Dosimetry is critical in advanced reactor designs, whether fission or fusion because the reactor systems are expected to sustain damage exceeding 30 dpa and to operate at temperatures ranging from 500 to 1000°C. And this type of damage and environment need tougher materials that will work properly and persist for the extended amount of time that modern reactors will be in operation. Even today's reactors, which have an average operational lifetime of roughly 40 years, are experiencing material wear and creep, let alone the expected 60 years [29].

Irradiation simulations are yet another key use of ion beam technology. Let us now have an overview of that.
