Re: A question on scintillation handling

Hi Ivana, thanks the output is indeed scintillation in my setup! All problems solved, just need to figure out the surface parameters for my fiber core and its enclosure in order to guide scintillation photons inside the fiber! Regarding this I have a probably newbie question. What is the difference between TVirtualMC::SetBorderSurface and TVirtualMC::SetSkinSurface? I assume that in any case I have to DefineOpSurface all my surfaces, correct? Regards, filimon

On 09/22/2010 12:56 PM, Ivana Hrivnacova wrote:
> Hi Filimon,
>
> I think, your previous problem was due to an incorrect build,
> as the break happens at a place where we have never seen a problem
> before.
>
> To see whether a photon comes from Cerenkov or scintillation, you can
> access its creator process code (see TMCProcess.h), which is saved for
> each particle in the stack as TParticle unique ID (this saving is done
> in Ex03MCStack::PushTrack).
> In the example E06, you can do following:
> #include <TParticle.h>
> #include <TMCProcess.h>
> //_____________________________________________________________________________
>
> void Ex06MCApplication::PreTrack()
> {
> /// User actions at beginning of each track
>
> fVerbose.PreTrack();
>
> if (gMC->TrackPid() == 50000050 ) {
> fGammaCounter++;
> Int_t mech = gMC->GetStack()->GetCurrentTrack()->GetUniqueID();
> cout << "Creator process: " << TMCProcessName[mech] << endl;
> }
> }
>
> If you then disable Cerenkov in g4config.in, you should see only
> Creator process: Scintillation
> Creator process: Scintillation
> ...
>
> Best regards,
>
> Ivana
>
> Filimon Roukoutakis wrote:
>> Hi Ivana,
>> after reporting to you the versions (privately) I decided to update
>> my geant4_vmc to r520. I do not know whether the problem could be
>> related to the old version or to a mis-built (mixed root versions
>> from previous build) of the vmc lib. In any case the problem now
>> seems to have disappeared. I get the following for example. Question:
>> Is Cerenkov really Cerenkov-produced or could it be scintillation
>> photos? Is there going to be a difference in the label? I see some
>> optical photons in the verbose output but do not know whether they
>> come from scintillation or Cerenkov. I have also disabled Cerenkov in
>> my g4config.in file but still get them. Thanks,
>> filimon
>>
>> *********************************************************************************************************
>>
>> * G4Track Information: Particle = opticalphoton, Track ID = 4,
>> Parent ID = 1
>> *********************************************************************************************************
>>
>>
>> Step# X(mm) Y(mm) Z(mm) KinE(MeV) dE(MeV) StepLeng
>> TrackLeng NextVolume ProcName
>> 0 -1.980e+02 9.062e-02 8.056e-04 3.140e-06 0.000e+00 0.000e+00
>> 0.000e+00 Fibe initStep
>> 1 -1.981e+02 6.756e-04 -2.530e-02 3.140e-06 0.000e+00 1.295e-01
>> 1.295e-01 Cell Transportation
>>
>> *********************************************************************************************************
>>
>> * G4Track Information: Particle = e-, Track ID = 3, Parent ID = 1
>> *********************************************************************************************************
>>
>>
>> Step# X(mm) Y(mm) Z(mm) KinE(MeV) dE(MeV) StepLeng
>> TrackLeng NextVolume ProcName
>> 0 -2.029e+02 1.883e-02 1.015e-02 6.250e-01 0.000e+00 0.000e+00
>> 0.000e+00 Shie initStep
>> 1 -2.027e+02 -3.523e-01 -3.991e-01 5.192e-01 1.059e-01 6.266e-01
>> 6.266e-01 Shie msc
>> 2 -2.024e+02 -4.455e-01 -6.059e-01 4.583e-01 6.081e-02 3.948e-01
>> 1.021e+00 Shie msc
>> 3 -2.022e+02 -6.466e-01 -5.628e-01 3.895e-01 6.884e-02 3.065e-01
>> 1.328e+00 Shie msc
>> 4 -2.020e+02 -7.650e-01 -5.473e-01 3.518e-01 3.766e-02 2.420e-01
>> 1.570e+00 Shie msc
>> 5 -2.019e+02 -8.432e-01 -4.498e-01 2.978e-01 5.403e-02 2.046e-01
>> 1.775e+00 Shie msc
>> 6 -2.018e+02 -8.205e-01 -3.497e-01 2.325e-01 6.533e-02 1.617e-01
>> 1.936e+00 Shie msc
>> 7 -2.017e+02 -7.609e-01 -2.431e-01 1.769e-01 5.554e-02 1.434e-01
>> 2.080e+00 Shie msc
>> 8 -2.017e+02 -7.662e-01 -1.076e-01 0.000e+00 1.769e-01 3.740e-01
>> 2.454e+00 Shie eIoni
>> 9 -2.017e+02 -7.662e-01 -1.076e-01 0.000e+00 0.000e+00 0.000e+00
>> 2.454e+00 Shie Scintillation
>>
>> *********************************************************************************************************
>>
>> * G4Track Information: Particle = gamma, Track ID = 2, Parent
>> ID = 1
>> *********************************************************************************************************
>>
>>
>> Step# X(mm) Y(mm) Z(mm) KinE(MeV) dE(MeV) StepLeng
>> TrackLeng NextVolume ProcName
>> 0 -2.045e+02 2.579e-03 -2.126e-03 3.628e-02 0.000e+00 0.000e+00
>> 0.000e+00 Shie initStep
>> 1 -2.018e+02 1.243e-02 -2.453e-02 0.000e+00 8.701e-04 2.647e+00
>> 2.647e+00 Shie phot
>>
>> *********************************************************************************************************
>>
>> * G4Track Information: Particle = e-, Track ID = 516, Parent ID
>> = 2
>> *********************************************************************************************************
>>
>>
>> Step# X(mm) Y(mm) Z(mm) KinE(MeV) dE(MeV) StepLeng
>> TrackLeng NextVolume ProcName
>> 0 -2.018e+02 1.243e-02 -2.453e-02 3.541e-02 0.000e+00 0.000e+00
>> 0.000e+00 Shie initStep
>> 1 -2.018e+02 2.109e-02 -2.345e-02 0.000e+00 3.541e-02 2.450e-02
>> 2.450e-02 Shie eIoni
>> 2 -2.018e+02 2.109e-02 -2.345e-02 0.000e+00 0.000e+00 0.000e+00
>> 2.450e-02 Shie Scintillation
>> --- Finish event
>> Stack Info
>> Total number of particles: 516
>> Number of primary particles: 1
>> TParticle: e- p: 0.080000 0.000000 0.000000 Vertex:
>> -3.000000e+02 0.000000e+00 0.000000e+00 -1 0
>> TParticle: e- p: 0.000636 -0.000393 -0.000722 Vertex:
>> 2.023844e+01 1.380119e+00 -9.969215e-01 0 1
>> TParticle: gamma p: 0.000220 0.000013 -0.000016 Vertex:
>> 2.010258e+01 1.367762e+00 -9.843252e-01 0 2
>> TParticle: gamma p: 0.000054 0.000004 -0.000003 Vertex:
>> 2.003232e+01 1.362088e+00 -9.787132e-01 0 3
>> TParticle: Cherenkov p: -0.000000 -0.000000 -0.000000 Vertex:
>> 1.956514e+01 1.336273e+00 -9.358289e-01 0 4
>> TParticle: Cherenkov p: -0.000000 0.000000 -0.000000 Vertex:
>> 1.956895e+01 1.336443e+00 -9.361586e-01 0 5
>> TParticle: Cherenkov p: 0.000000 -0.000000 0.000000 Vertex:
>> 1.924589e+01 1.321851e+00 -9.082567e-01 0 6
>> TParticle: Cherenkov p: -0.000000 -0.000000 0.000000 Vertex:
>> 1.881176e+01 1.300382e+00 -8.703480e-01 0 7
>> TParticle: Cherenkov p: -0.000000 -0.000000 -0.000000 Vertex:
>> 1.875277e+01 1.297413e+00 -8.649779e-01 0 8
>> TParticle: Cherenkov p: -0.000000 0.000000 -0.000000 Vertex:
>> 1.873954e+01 1.296666e+00 -8.637950e-01 0 9
>> TParticle: Cherenkov p: -0.000000 -0.000000 0.000000 Vertex:
>> 1.871651e+01 1.295366e+00 -8.617343e-01 0 10
>> TParticle: Cherenkov p: -0.000000 0.000000 0.000000 Vertex:
>> 1.873194e+01 1.296237e+00 -8.631147e-01 0 11
>> TParticle: Cherenkov p: 0.000000 0.000000 0.000000 Vertex:
>> 1.871305e+01 1.295171e+00 -8.614247e-01 0 12
>> TParticle: Cherenkov p: 0.000000 0.000000 -0.000000 Vertex:
>> 1.873276e+01 1.296283e+00 -8.631885e-01 0 13
>> TParticle: Cherenkov p: 0.000000 -0.000000 -0.000000 Vertex:
>> 1.823852e+01 1.270792e+00 -8.154165e-01 0 14
>> TParticle: Cherenkov p: -0.000000 -0.000000 -0.000000 Vertex:
>> 1.826841e+01 1.272338e+00 -8.185104e-01 0 15
>> TParticle: Cherenkov p: -0.000000 0.000000 -0.000000 Vertex:
>> 1.820691e+01 1.268963e+00 -8.122148e-01 0 16
>> TParticle: Cherenkov p: -0.000000 0.000000 -0.000000 Vertex:
>> 1.818631e+01 1.267756e+00 -8.101328e-01 0 17
>> TParticle: Cherenkov p: -0.000000 -0.000000 0.000000 Vertex:
>> 1.821648e+01 1.269523e+00 -8.131813e-01 0 18
>> TParticle: Cherenkov p: 0.000000 -0.000000 0.000000 Vertex:
>> 1.812218e+01 1.263938e+00 -8.033476e-01 0 19
>> TParticle: Cherenkov p: -0.000000 -0.000000 -0.000000 Vertex:
>> 1.785667e+01 1.247947e+00 -7.732789e-01 0 20
>> TParticle: Cherenkov p: 0.000000 0.000000 -0.000000 Vertex:
>> 1.775054e+01 1.242225e+00 -7.610460e-01 0 21
>>
>>
>>
>> On 09/21/2010 09:03 PM, Ivana Hrivnacova wrote:
>>>
>>> Dear Filimon,
>>>
>>> It is difficult to see what gets wrong just from the back trace;
>>> could you run with /tracking/verbose 1 and send me the end of file
>>> with a few tracks?
>>> Also, what are the versions of everything (root, geant4, geant4_vmc)
>>> and what is your physics list selection?
>>>
>>> Best regards,
>>>
>>> Ivana
>>>
>>> Filimon Roukoutakis wrote:
>>>> Dear Ivana, thanks for all this information. I have started my
>>>> implementation and at the moment I get the following output.
>>>> I assume this happens right when starting to track optical photons
>>>> because by enabling more G4-native verbosity I can see that I have
>>>> some optical photons created (and presumably put in the stack, so
>>>> the scintillation mechanism part seems to work...). Any hint on
>>>> where to look for the problem? The problem occurs in my case even
>>>> if I comment out all my optical geometry code, the thing that
>>>> triggers it is the addition of "+optical" to my
>>>> TG4Runconfiguration... The N06 example runs properly even after
>>>> enabling scintillation, so I guess I miss something from the
>>>> example in my code.
>>>> filimon
>>>>
>>>> *** Break *** floating point exception
>>>>
>>>>
>>>>
>>>> ===========================================================
>>>> There was a crash (#7 0x00a7136d in SigHandler(ESignals) () from
>>>> /opt/root/v5-27-04/lib/libCore.so.5.27).
>>>> This is the entire stack trace of all threads:
>>>> ===========================================================
>>>> #0 0x006cd422 in __kernel_vsyscall ()
>>>> #1 0x05e997d3 in __waitpid_nocancel () at
>>>> ../sysdeps/unix/syscall-template.S:82
>>>> #2 0x05e3ade3 in do_system (line=<value optimized out>) at
>>>> ../sysdeps/posix/system.c:149
>>>> #3 0x0039327d in system (line=0xbce79c0
>>>> "/opt/root/v5-27-04/etc/gdb-backtrace.sh 16138 1>&2") at
>>>> pt-system.c:29
>>>> #4 0x00a6981d in TUnixSystem::Exec(char const*) () from
>>>> /opt/root/v5-27-04/lib/libCore.so.5.27
>>>> #5 0x00a6fed5 in TUnixSystem::StackTrace() () from
>>>> /opt/root/v5-27-04/lib/libCore.so.5.27
>>>> #6 0x00a71265 in TUnixSystem::DispatchSignals(ESignals) () from
>>>> /opt/root/v5-27-04/lib/libCore.so.5.27
>>>> #7 0x00a7136d in SigHandler(ESignals) () from
>>>> /opt/root/v5-27-04/lib/libCore.so.5.27
>>>> #8 0x00a66a32 in sighandler(int) () from
>>>> /opt/root/v5-27-04/lib/libCore.so.5.27
>>>> #9 <signal handler called>
>>>> #10 0x0595718a in G4VProcess::AtRestGPIL (this=0xba37360,
>>>> track=..., condition=0xa394118) at
>>>> /home/filimon/geant4.9.3/source/processes/management/include/G4VProcess.hh:456
>>>>
>>>> #11 0x05955cd2 in G4SteppingManager::InvokeAtRestDoItProcs
>>>> (this=0xa394010) at src/G4SteppingManager2.cc:298
>>>> #12 0x05952d5b in G4SteppingManager::Stepping (this=0xa394010) at
>>>> src/G4SteppingManager.cc:160
>>>> #13 0x0595eff3 in G4TrackingManager::ProcessOneTrack
>>>> (this=0xa393fe8, apValueG4Track=0xbce69c8) at
>>>> src/G4TrackingManager.cc:126
>>>> #14 0x028695f0 in G4EventManager::DoProcessing (this=0xa393fa0,
>>>> anEvent=0xb7bcf00) at src/G4EventManager.cc:185
>>>> #15 0x02869d18 in G4EventManager::ProcessOneEvent (this=0xa393fa0,
>>>> anEvent=0xb7bcf00) at src/G4EventManager.cc:335
>>>> #16 0x052349c0 in G4RunManager::DoEventLoop (this=0xa393e68,
>>>> n_event=10, macroFile=0x0, n_select=-1) at src/G4RunManager.cc:235
>>>> #17 0x052343a8 in G4RunManager::BeamOn (this=0xa393e68, n_event=10,
>>>> macroFile=0x0, n_select=-1) at src/G4RunManager.cc:140
>>>> #18 0x05d96677 in TG4RunManager::ProcessRun (this=0xa3d2ad8,
>>>> nofEvents=10) at run/src/TG4RunManager.cxx:397
>>>> #19 0x05d9af17 in TGeant4::ProcessRun (this=0xa3ca390,
>>>> nofEvents=10) at run/src/TGeant4.cxx:1179
>>>> #20 0x058d7f46 in TMCApplication::RunMC (this=0xa35cca0,
>>>> nEvents=10) at TMCApplication.cpp:126
>>>>
>>>>
>>>> On 09/20/2010 11:05 AM, Ivana Hrivnacova wrote:
>>>>>
>>>>> Dear Filimon,
>>>>>
>>>>> The examples in VMC implement the same setting (the same as it was
>>>>> at the time when we did this work) as the novice examples in Geant4.
>>>>>
>>>>> The parameters which are in geant4_vmc preceded with the comment:
>>>>> // Added (for Geant3)
>>>>> are not needed in Geant4 (and they are not present in Geant4
>>>>> native example N06) and were added in order to get the example
>>>>> working with Geant3, where all three sets of parameters for
>>>>> Cerenkov process are always requested (see
>>>>> TVirtualMC::SetCerenkov(...)). Note, that they have special values
>>>>> (DBL_MAX for absorption and 0. for efficiency).
>>>>>
>>>>> The scintillation is inactivated in the macro as it is also
>>>>> inactivated in Geant4 native example in the default macro.
>>>>>
>>>>> The Birks correction is implemented in G4Scintillation.cc since
>>>>> G4.9.2
>>>>> (see:
>>>>> http://hypernews.slac.stanford.edu/HyperNews/geant4/get/opticalphotons/311/1.html)
>>>>>
>>>>> what was after the implementation of the examples in VMC,
>>>>> that's why the setting of the Birk constant to the material, which
>>>>> you can find in Geant4 native example is missing in the VMC example.
>>>>> As this setting is done in a different way than the setting of
>>>>> other material properties, it will need a special support in the
>>>>> VMC interface. I will have a look at it and let you know when this
>>>>> is available.
>>>>>
>>>>> Geant3 does not include scintillation process at all.
>>>>>
>>>>> Best regards,
>>>>>
>>>>> Ivana
>>>>>
>>>>>
>>>>>
>>>>> Filimon Roukoutakis wrote:
>>>>>> Dear all,
>>>>>> I am going through example E06 of geant4_vmc tarball. Trying to
>>>>>> simulate a lead/scint fiber calorimeter (now moving to the
>>>>>> optical part as the energy deposition seems correct according to
>>>>>> data comparison) I have an initial question.
>>>>>> In the Ex06DetectorConstruction.cxx file in the
>>>>>> ConstructOpProperties method there are some comments like "Added
>>>>>> (for Geant3)". Since I do not know to which set of properties
>>>>>> they apply (only for efficiency?), my question is, are these only
>>>>>> used by G3 back-end, in the sense that G4 handles them
>>>>>> differently? If yes, by which mechanism? I see that in the
>>>>>> provided g4config.in file the scintillation is deactivated. In my
>>>>>> use-case should I then enable this (or simply delete the lines)
>>>>>> and provide all the G3 information that is in the
>>>>>> ConstructOpProperties in a G4 format in the g4config file or are
>>>>>> the fields under "Added (for Geant3)" also applicable for G4 (I
>>>>>> am obviously interested for the yield/MeV and the slow/fast
>>>>>> component arrays and ratio/settings). To summarize, if I just
>>>>>> remove the line about disabling scintillation in the g4.in file,
>>>>>> will scintillation work correctly for both G3 _and G4 with
>>>>>> something similar to the example code (provided ofcourse that I
>>>>>> use the proper values for my scintillating material where
>>>>>> applicable...)?
>>>>>> A more advanced but related question is whether there is some
>>>>>> provision for birk's law under G3 or G4. Any provision/experience
>>>>>> on this?
>>>>>> Thanks,
>>>>>> filimon
>>>>>
>>>>
>>>
>>
>