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Radionuclide decay and daughter build-up

Posted: January 10th, 2018, 3:23 am
by blake.arpansa
Is it possible to configure HYSPLIT to follow daughter nuclides through a decay chain?

For example the 131 chain.
Sb131 -> Te131 -> I-131.
The I-131 slowly builds up after the first few hours following fission, using the initial I-131 an result in an underestimate.


Re: Radionuclide decay and daughter build-up

Posted: January 12th, 2018, 2:19 pm
by ariel.stein
Yes, it is possible to calculate daughter products using hysplit.

If you run HYSPLIT through the GUI, setting up this run consists in the following steps.

Step 1: Define the nuclide parent name (e.g. Cs-137) and run a preprocessor
(nuctree) that creates a summary text file (DAUGHTER.TXT) that contains
the daughter nuclides produced by a parent nuclide along with the half-life
and branching fractions. This file is required to be in the working
directory when running HYSPLIT for this application.
In addition, the preprocessor will read the CONTROL file and create a new
(CONTROL.DAUGHTER) file containing the daughter information. The names
of the species will be given in numbers that correspond to the daughter
products names written in the DAUGHTER.TXT file.
Finaly, the GUI will copy the CONTROL.DAUGHTER back to CONTROL.

Step 2: configure setup (SETUP.CFG) indicating that the daughter products module will
be used (ICHEM=11) and set Maxdim=#daughters obtained from DAUGHTER.TXT