Keyword:MASS

MASS totm indx2
sym(i) xp(i) i=1,indx2

---

This keyword allows the input of the total mass totm (kg) and the number (indx2) of elements in the material to be irradiated. For each element the chemical symbol sym(i), e.g. ‘Fe’, and the percentage by weight, xp(i), are then read. This keyword enables elements to be input with the number of atoms of each isotope calculated by FISPACT-II using natural abundance data that are stored internally. If an element whose natural abundances are not known is selected, then FISPACT-II will issue a fatal error message. Computations for these cases must use the FUEL keyword and specify the individual isotopic inventories.

Note that FUEL and MASS cannot be both used in the same input file. It is also not essential that the total of all elements is exactly 100%, however if the total was say 80% and 1 kg was specified for totm, then only 800 g of material would be considered in the calculation. It is recommended that the user ensures that the total percentage of all elements equals 100%.

Example usage:

< -- Control phase -- >
...
FISPACT
* Title of the simulation
< -- Initial phase -- > 
MASS 1.0 7
 Fe 65.255
 Cr 18.0
 Ni 12.015
 Mo 2.4
 Mn 1.8
 Si 0.5
 C 0.03
...
< -- Inventory phase -- > 
...