information about tallies of macroscopic reaction rates

User Support
1

Hello,

Talling separately reaction rates per nuclide is indicated in section 8.2 of the documentation available online (v0.11.0).
It does not seem possible to score macroscopic reaction rates (i.e. the reaction rates determined as the sum on reactions of all existing nuclides in the specified volume or region filtered in the phase space) according to this documentation. Please, can you confirm?
If this option is possible, what is the keyword that users should enter?
Thanks for your kind attention.
Best regards,

Shai

2

Hi Shai,

As you say, reaction rates per nuclide can be specified e.g. by

tally = openmc.Tally()
tally.scores = [‘absorption’, ‘nu-fission’]
tally.nuclides = [‘U235’, ‘U238’]

However, if you simply leave out the “tally.nuclides” specification, then you will get the total reaction rate summed over all the nuclides in the material:

tally = openmc.Tally()
tally.scores = [‘absorption’, ‘nu-fission’]

3

Thanks Sterling!