Problem 2021

Summary: hadElastic process energy conservation of low energetic hadrons
Product: Geant4 Reporter: Laurent K <laurent.kelleter.16>
Component: processes/hadronic/models/coherent_elasticAssignee: Vladimir.Ivantchenko
Status: RESOLVED FIXED    
Severity: normal    
Priority: P4    
Version: 10.4   
Hardware: All   
OS: Linux   

Description Laurent K 2017-12-14 13:03:48 CET 
The hadElastic process of low-energetic particles seems to violate energy conservation. In my simulation I see low-energetic protons and neutrons (e.g 6.7572e-09 MeV) creating a higher-energetic proton (e.g. 1.34535 MeV) in a hadElastic interaction with a hydrogen atom.

I am using Geant4v10.2 on scientific Linux. I simulate a proton beam in water using the physicslist QGSP_BIC with emstandard_opt3. The step maximum is 0.5mm and the range cut is 1mm.
Comment 1 Vladimir.Ivantchenko 2019-04-17 19:09:20 CEST 
Hello,

Sorry for the late answer. I just check with the recent Geant4 10.5, that 6.757e-9 MeV neutron does not provide energy non-conservation in the default hadron elastic scattering with QGSP_BIC. I would guess, that the problem was fixed long ago - in the code there is a special treatment for low energy hadronic projectile.

VI