I would like to separate prompt gammas produced at the time of neutron capture from delayed gammas emitted later due to radioactive decay of the activated nuclei.
Which physics settings are recommended to obtain the gamma energy spectrum and yield from activated materials, and how should these results be properly normalized (e.g. per incident neutron or per second)?
Thank you for the question and welcome to the forum!
I would like to separate prompt gammas produced at the time of neutron capture from delayed gammas emitted later due to radioactive decay of the activated nuclei.
Prompt gammas: use a USRTRACK card for the region of interest.
Delayed gammas: use in addition a DCYSCORE card to link a separate USRTRACK card with a given cooling time (see DCYTIMES). In this case, the RADDECAY card and an irradiation profile input through IRRPROFI should be present too.
Which physics settings are recommended to obtain the gamma energy spectrum and yield from activated materials … ?
The following cards should be activated:
PHYSICS with SDUM = COALESCE and WHAT(1) = 1.0 - to activate the coalescence treatment.
PHYSICS with SDUM = EVAPORAT and WHAT(1) = 3.0 - to enable the evaporation of heavy fragments.
Please ensure that you run with flukadpm or link the RQMD and DPMJET libraries by ldpmqmd if generating a custom executable.
… how should these results be properly normalized (e.g. per incident neutron or per second)?
When scoring fluence with USRTRACK, the results will be in (\text{cm}^{-2}\text{GeV}^{-1} / primary) if the region volume is provided. If no region volume is provided, the results are given in track length (cm/primary).
Once the USRTRACK detector is linked with a cooling time via a DCYSCORE card, the fluence will be expressed per unit time instead of per primary.