Problem 1002

Created attachment 18 [details]
Output for standard and LowEnergy librarys

Hello,

this is a copy of my posting in the User Forum for electromagnetic processes:

On Fri, 22 Feb 2008, Robert wrote:

> *** Discussion title: Electromagnetic Processes
> Email replies to PublicHyperNews@slac.stanford.edu must include:
>   In-Reply-To: <"/emprocess/812"@geant4-hn.slac.stanford.edu>
>   Subject: ...change this to be about your reply.
> 
> Dear all,
> 
> I've the problem, that I get too much energy! My aim is to simulate the
> energy deposition in 100 um thick spherical shells around a point source
> of 500 keV electrons. When I use the standard Geant4 librarys for
> electromagnetic processes everything works fine, as you can see below:
> 
> Extraction of MyPhysicsList.cc
> 
>   if(particleName == "gamma")
>     {
>       //gamma
>       pMan->AddDiscreteProcess(new G4PhotoElectricEffect);
>       pMan->AddDiscreteProcess(new G4ComptonScattering);
>       pMan->AddDiscreteProcess(new G4GammaConversion);
>     }
>   else if(particleName == "e-")
>     {
>       //electron
>       pMan->AddProcess(new G4MultipleScattering, -1, 1, 1);
>       pMan->AddProcess(new G4eIonisation, -1, 2, 2);
>     }
>   else if(particleName == "e+")
>     {
>       //positron
>       pMan->AddProcess(new G4MultipleScattering, -1, 1, 1);
>       pMan->AddProcess(new G4eIonisation, -1, 2, 2);
>       pMan->AddProcess(new G4eBremsstrahlung, -1, 3, 3);
>       pMan->AddProcess(new G4eplusAnnihilation, 0, -1, 4);
>      }
> 
> The results look as expected:
> 
> ******Run 0 finished! 
>    Simulated events: 1
>  Shell[0]   E_abs: 20.0067911778766 keV   
>  Shell[1]   E_abs: 18.46432871484156 keV   
>  Shell[2]   E_abs: 17.16755680496905 keV   
>  Shell[3]   E_abs: 15.4193391766694 keV   
>  Shell[4]   E_abs: 23.61578150214196 keV   
>  Shell[5]   E_abs: 20.47036611695079 keV   
>  Shell[6]   E_abs: 98.07545602952851 keV   
>  Shell[7]   E_abs: 134.2114403391701 keV   
>  Shell[8]   E_abs: 152.5689401378521 keV   
>  Shell[9]   E_abs: 0 eV
>  Shell[10]   E_abs: 0 eV 
>     total absorbed energy: 500 keV
> 
> When I change to the LowEnergy package in MyPhysicsList.cc via:
> 
>   if(particleName == "gamma")
>     {
>       //gamma
>       pMan->AddDiscreteProcess(new G4LowEnergyRayleigh);
>       pMan->AddDiscreteProcess(new G4LowEnergyPhotoElectric);
>       pMan->AddDiscreteProcess(new G4LowEnergyCompton);
>       pMan->AddDiscreteProcess(new G4LowEnergyGammaConversion); 
>     }
>   else if(particleName == "e-")
>     {
>       //electron
>       pMan->AddProcess(new G4MultipleScattering, -1, 1, 1);
>       pMan->AddProcess(new G4LowEnergyIonisation, -1, 2, 2);
>       pMan->AddProcess(new G4LowEnergyBremsstrahlung, -1, 3, 3);
>     }
>   else if(particleName == "e+")
>     {
>       //positron
>       pMan->AddProcess(new G4MultipleScattering, -1, 1, 1);
>       pMan->AddProcess(new G4eplusAnnihilation, 0, -1, 4);
>       pMan->AddProcess(new G4LowEnergyIonisation, -1, 2, 2);
>       pMan->AddProcess(new G4LowEnergyBremsstrahlung, -1, 3, 3);
>     }
> 
> then I got via the G4PSEnergyDeposit-scorer a total absorbed energy of
> 561.4 keV.
> 
> ******Run 0 finished! 
>    Simulated events: 1
>  Shell[0]   E_abs: 32.46440622087332 keV
>  Shell[1]   E_abs: 28.14419079032732 keV
>  Shell[2]   E_abs: 35.09535948072306 keV
>  Shell[3]   E_abs: 66.8380046101959 keV 
>  Shell[4]   E_abs: 45.85848368358489 keV 
>  Shell[5]   E_abs: 48.56747246418793 keV 
>  Shell[6]   E_abs: 51.08569021249662 keV 
>  Shell[7]   E_abs: 166.0850614863725 keV 
>  Shell[8]   E_abs: 87.2664894852086 keV 
>  Shell[9]   E_abs: 0 eV 
>  Shell[10]   E_abs: 0 eV 
>     total absorbed energy: 561.4051584339702 keV
> 
> I already found, that the problem results from an energy loss dE which
> is twice the kinetic energy KinE of my particle as you can see by a
> detailed output of tracking:
> 
> *********************************************************************************************************
> * G4Track Information:   Particle = e-,   Track ID = 16,   Parent ID = 1
> *********************************************************************************************************
> 
> Step#    X(mm)    Y(mm)    Z(mm) KinE(MeV)  dE(MeV) StepLeng TrackLeng  NextVolume ProcName
>     0   -0.419    0.624   -0.239   0.00145        0        0         0 shell_physical[] initStep
>     1   -0.419    0.624   -0.239         0   0.0029   0.0215    0.0215 shell_physical[] msc
> 
> *********************************************************************************************************
> * G4Track Information:   Particle = e-,   Track ID = 15,   Parent ID = 1
> *********************************************************************************************************
> 
> Step#    X(mm)    Y(mm)    Z(mm) KinE(MeV)  dE(MeV) StepLeng TrackLeng  NextVolume ProcName
>     0   -0.387    0.659   -0.298   0.00317        0        0         0 shell_physical[] initStep
>     1   -0.387    0.659   -0.298         0  0.00634   0.0155    0.0155 shell_physical[] LowEnergyIoni
> 
> Does anyone knows this problem and perhaps how to solve it?
> 
> Thanks for your help
> 
> best regards, Robert
> 
> system: geant4.9.1, G4EMLOW5.1

I will attach the output file for both librarys. In the first part the standard librarys were used and in the second part of the output file the LowEnergy classes were used for simulation.
Please excuse some German words in the file, but I hope this wouldn't be an obstacle to understand the problem.

Best regards,

Robert Freudenberg