Pointwise neutron cross section

Dear FLUKA experts,
I’m trying to activate the pointwise neutron cross section for BORON-10 in the thermal neutron region, since I’m interested in the 478keV emitted due to neutron capture. The pointwise cross section of B-10 should be present according to table 10.5.5 in the Manual. In my simulation, I set DEFAULT to PRECISIOn and I added a LOW-NEUT card with WHAT(6)=4.

  1. The following are the scoring using USRTRACK, in which you can see that the interested gamma is not monoenergetic. I would expect it to be monoenergetic at 478 keV, am I wrong?

  2. The output says that the only pointwise cross section activated is the H-1 one:
    output
    I thought about using LOW-PWXS card but it looks like it’s not supported by Flair. Is there a way to check if the B-10 pointwise cross section is engaged correctly?

Thank you in advance,
Giacomo

DETECT + RADDECAY tests.inp (4.0 KB)

Dear @JackColombo

  1. Your simulation is correct. FLUKA does create a monoenergetic 478keV gamma following the 10B(n,α)7Li in the center of mass system (CMS). However the recoil nucleus 7Li has a considerable energy after the (n,α) reaction, which smears the gamma energy when it is boosted back to the lab (either gain or lose energy). You get a flat distribution, since in absence of any other information the gamma is emitted isotropically in the CMS frame.
  2. Unfortunately there is nothing printed in the output to indicate that the 10B PW treatment is active. The LOW-PWXS is intended for running fully point-wise simulations. Is not currently active in the 4.2.x but it will be available in the next release.
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Thank you so much for your clear answer!

Giacomo