I am trying to reproduce the fig 2 of the attached document using FLUKA. After applying proper conversion from lab to cm frame, it is observed that the simulation result at forward angle is very high as compared to the experimental value. More over, the literature suggests a pronounced peak at 10 - 12 MeV, which is not observable from fluka simulation.
It will be helpful if it is possible to provide any explanation for this.
The considered paper and figure refer to the specific (d,n) channel, while you are scoring neutrons from any open channel, including also (d,2n) and (d,np).
In this regard, note that FLUKA is not designed to extract microscopic cross-sections (that are regularly benchmarked at the level of the respective model implementation), rather to quantify macroscopic effects (such as energy deposition, particle fluence, material activation, physics signals, etc.).