Neutron attenuation in borated polyethylene

Dear FLUKA experts,

I am trying to calculate the neutron attenuation in BPE but somehow, my results are not in good agreement with literature. I had define the material composition in the input file with the information found on google. Does anyone had this kind on issue when using BPE or does anyone has the correct chemical composition of 5% BPE that could share? Thanks!

Dear Roxana,

could you share your Flair project file, and the literature (or a link to it) you are comparing your results to?