Production of radioactive nuclides when stable atoms absorb neutrons. In reactors, cobalt-59 in steel and hardfacing alloys becomes cobalt-60, nickel produces cobalt-58 and iron produces iron-59, both in core structures and in corrosion products that pass through the core. Activation products dominate plant dose rates and decommissioning waste, which is why low-cobalt materials are specified for components in contact with reactor coolant.
Most of the dose on that valve is activation products in the crud, cobalt-60 and cobalt-58.
Also heard as
- neutron activation
Related terms
Crud
Corrosion products that deposit on fuel and in reactor piping, become radioactive and drive most plant dose.
Half-life
The time it takes for half the atoms of a radioactive isotope to decay, a fixed value for each nuclide.
Hot spot
A small spot on piping or equipment with a much higher dose rate than its surroundings.
Radwaste
Radioactive waste produced by nuclear facilities, and the plant department that processes and ships it.