18.17} Radioactivity evolution and radioactive decays

 -----------------------------------------------------

 FLUKA is capable of making predictions about residual nuclei following
 hadronic and electromagnetic showers since late 1994. The accuracy of
 these predictions steadily improved along the years, in particular after
 the introduction of the new evaporation/fragmentation and the improvements
 and extensions of the PEANUT model: versions before end 1996 were unlikely
 to give satisfactory results. Of course, all FLUKA versions prior to
 1989 were totally unable to formulate predictions on this issue.
 Since 1995, an offline code by Ferrari was distributed together with FLUKA,
 which allowed to compute offline the time evolution of a radionuclide
 inventory computed with FLUKA, for arbitrary irradiation profiles and decay
 times. In 2004--2005, this capability has been brought online by Ferrari
 and Sala, with an exact analytical implementation (Bateman equations)
 of the activity evolution during irradiation and cooling down, for
 arbitrary irradiation conditions. Furthermore, the generation and
 transport of decay radiation (limited to gamma, beta-, and beta+
 emissions for the time being) is now possible. A dedicated database
 of decay emissions has been created by Ferrari and Sala, using mostly
 informations obtained from NNDC, sometimes supplemented with other data
 and checked for consistency.
 As a consequence, results for production of residuals, their time evolution
 and residual doses due to their decays can now be obtained in the same run,
 for an arbitrary number of decay times and for a given, arbitrarily complex,
 irradiation profile.

Previous Index Next