Problem 1188 - NeutronHP inelastic process producing nonsensical gammas with Cu target
Summary: NeutronHP inelastic process producing nonsensical gammas with Cu target
Status: RESOLVED INVALID
Alias: None
Product: Geant4
Classification: Unclassified
Component: processes/hadronic/models/neutron_hp (show other problems)
Version: 9.4
Hardware: Apple Mac OS X
: P4 major
Assignee: tkoi
URL:
Depends on:
Blocks:
 
Reported: 2011-04-05 08:35 CEST by jasondet
Modified: 2012-10-30 23:10 CET (History)
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Description jasondet 2011-04-05 08:35:12 CEST 
I am having a problem in neutron HP. I'm using G4.9.4p01 with CLHEP 2.1.0.1 and G4NDL3.14. I can isolate the problem using examples/extended/hadronic/Hadr00. If I give it a macro that shoots several-MeV neutrons at a target of Cu, we get some very strange gammas. For example, using 4 MeV neutrons and turning tracking verbosity to 2, we see inelastic interactions like this:

*********************************************************************************************************
* G4Track Information:   Particle = neutron,   Track ID = 1,   Parent ID = 0
*********************************************************************************************************

Step#    X(mm)    Y(mm)    Z(mm) KinE(MeV)  dE(MeV) StepLeng TrackLeng  NextVolume ProcName
    0        0        0        0         4        0        0         0      Target initStep
    1        0        0     14.2      3.81        0     14.2      14.2      Target hadElastic
    :----- List of 2ndaries - #SpawnInStep=  1(Rest= 0,Along= 0,Post= 1), #SpawnTotal=  1 ---------------
    :         0         0      14.2     0.186          Cu65[0.0]
    :----------------------------------------------------------------- EndOf2ndaries Info ---------------
    2   0.0336  -0.0621     14.1         0        0   0.0831      14.3      Target NeutronInelastic
    :----- List of 2ndaries - #SpawnInStep=  5(Rest= 0,Along= 0,Post= 5), #SpawnTotal=  6 ---------------
    :    0.0336   -0.0621      14.1     0.803            neutron
    :    0.0336   -0.0621      14.1    0.0664          Cu63[0.0]
    :    0.0336   -0.0621      14.1      1.14              gamma
    :    0.0336   -0.0621      14.1     0.903              gamma
    :    0.0336   -0.0621      14.1     0.903              gamma
    :----------------------------------------------------------------- EndOf2ndaries Info ---------------
Track (trackID 1, parentID 0) is processed with stopping code 2

The 1.14 MeV gamma and the two at 903 keV don't correspond to any transitions in Cu63. Interestingly, if I change the target to another material like Pb or Ge the gammas that are produced look more reasonable.

Thanks,
Jason
Comment 1 tkoi 2011-05-12 02:17:47 CEST 
Hi Jason,

This a kind of a feature of NeutronHP.
However there is some space for improvment.
So let me give some time.

Thank you very much.

Tatsumi