|Message: On Low Energy Neutron Scattering- Help needed||Not Logged In (login)|
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So I have been reading a lot about the geant4 physics lists and I understand that for low energy you need to use the High Precision Neutron Package and not the Electromagnetic Variation EMV package. But there is also a Physics List called HPThermalScattering that shows results completely different from the HP or EMV model. For example, when i am launching a set of 10000 neutrons in Aluminium then for the HPThermalScattering the number of scattering events over the Aluminium increases as the neutron energy increases from .2 meV to 1000 meV and since the scattering cross section for neutron scattering in Aluminium decreases as energy increases from .2 to 1000 meV, as shown here: http://www.nndc.bnl.gov/sigma/getPlot.jsp?evalid=4230&mf=3&mt=2&nsub=10, this is clearly not right.
And so I was thinking that for this situation the High Precision Model HP, such as in the case of Physics List QGSP_BERT_HP is the best list to use. But I had thought that HP ThermalScattering was supposed to be used for these kind of experiments, with neutrons of thermal energy or lower. I was thinking that HP ThermalScattering was perhaps specifically designed for certain particles and materials and I was wondering if that is true. Does the material you are measuring scattering and capture events in affect which is better, HPElastic or HP ThermaScattering ? It hard to tell since HP models like QGSP_BERT_HP and HPThermalScattering are both supposed to be used at energies below the MeV order of magnitude.
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