|Message: No low-energy resonances in beryllium photo-nuclear cross section?||Not Logged In (login)|
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Hello, I've been using LHEP_PRECO_HP to simulate the production of neutrons from electron beams below 20 MeV interacting in various targets (via the photo-nuclear interaction), for comparison to experimental data and other MC packages. From what I can gather, the cross section for different materials is calculated in G4PhotoNuclearCrossSection::GetCrossSection(), based on the parameters of the giant dipole resonance. This is fine for interactions where this broad resonance (which peaks well beyond 20 MeV) dominates, but for beryllium there are additional (and prominent) very low energy resonances in the 2 MeV to 4 MeV region which are not (and cannot be) described by the parameters of this resonance. As a result, the production of neutrons for Be targets is well below expectation: one order of magnitude low at 20 MeV, and two orders at 10 MeV. Is there any plan to include these resonances in the cross-section calculation in the near future, or should I try to implement something in the code to account for the missing resonances myself? Many thanks. Cheers, Pat
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