"Migration Area" is the sum of the slowing-down area from fission energy to thermal energy and the diffusion area for thermal neutrons.
Applicable units are those of quantitykind:Area
http://encyclopedia2.thefreedictionary.com/migration+area
"Migration Area" is the sum of the slowing-down area from fission energy to thermal energy and the diffusion area for thermal neutrons.
http://www.iso.org/iso/catalogue_detail?csnumber=31895