MCNP source definition question

[llatosz]

I'm modelling a scenario for the research that I'm working on, and I got the cells and surfaces all mapped out for the environment finally, but now I'm totally stuck on creating a source.
I'd like a point source of Californium-252, but after hours of looking, I don't see any out of the 1000 examples in the manual that covers SDEF for a source that can emit different particles!

I have it in MODE N P, but I don't see how you would go about defining the source to spit out 2 different particle types, each with their own energy spectrum.

Anybody know how to make a Ca-252 source in MCNP? You would be a true savior! :)

 

[PSRB191921]

For my part for the neutron Spectrum I use a Watt Spectrum for Cf252 :

"mode n p
sdef par=n pos 0 0 0 erg d1
sp1 -3 1.025 2.926"

I use a "mode p n" to transport neutrons and to generate gamma capture (n,g reactions) and to transport them.
The result is for one neutron emitted.
I never use the possibility to emitte two different particles because the normalisation of the result is difficult

 

[rpp]

One idea is to run two calculations - one with a neutron source, and one with a gamma source - then add them together.
You will have to weight the two calculations depending on what the initial sources are.

For example, if you had a source that emitted X neutrons and Y gammas, then run gamma and neutron calculation separately.
The final result would be X times the neutron answer plus Y times the gamma answer.

 

[llatosz]

For my part for the neutron Spectrum I use a Watt Spectrum for Cf252 :

"mode n p
sdef par=n pos 0 0 0 erg d1
sp1 -3 1.025 2.926"

I use a "mode p n" to transport neutrons and to generate gamma capture (n,g reactions) and to transport them.
The result is for one neutron emitted.
I never use the possibility to emitte two different particles because the normalisation of the result is difficult

This worked very well and was actually what my coworker suggested too! Thank you very much