MCNP: Ctme Card Impacts on Results

Thread starter Salman Khan
Start date Jun 12, 2023
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Mcnp

AI Thread Summary

The Ctme card in MCNP limits the running time of the input file, directly impacting the tally results. When the time limit is exceeded, only the number of particles run up to that point is used for the tallies. Sufficient particle counts can yield reliable statistics, while insufficient counts can result in poor statistical outcomes. Therefore, the effectiveness of the tallies is contingent on the number of particles processed within the time constraint. Overall, managing the Ctme card is crucial for obtaining accurate results in MCNP simulations.

Jun 12, 2023

Salman Khan

Ctme card is used to limit the running time of the mcnp input file, does it affect the telly result or not ?

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Jun 12, 2023

Grelbr42

Yes.

In that whatever number of particles have been run when the time is exceeded is what is used in the tallies. If you have enough particles to get good stats, great! If not, then you get bad stats on that run.

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