Empty Histograms in Modified XrayFluorescence Example

Getting Started
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Geant4 Version: 11.3.2
Operating System: Ubuntu
Compiler/Version: g++ 13.3.0
CMake Version: 3.28.3

Problem Statement:
I am using the Geant4 advanced example XrayFluo to simulate X-ray fluorescence, but output histograms h1, 5, 6, 8, and 9 are empty, even though the simulation appears to run normally and completes without runtime errors and populates histograms 2, 3, 4, and 7.

Steps to Reproduce:

  1. Build the XrayFluo example with the vis.mac and initInter.mac execution lines of XrayFluoSimulation.cc commented out (executing livermore.mac with the stock .cc file ran into batch interruptions at /addPhysics.
  2. Launch interactive mode and execute livermore.mac.
  3. After running the simulation, check the output histogram files (ROOT or text).

What I Have Tried:

  • Confirmed that physics setup commands are executed before initialization (the vis.mac and initInter.mac calls in XrayFluorSimulation.cc have been commented out; they were causing interruption errors when livermore.mac tried to add physics packages).
  • Verified that XrayFluoPhysicsList and related messengers are properly included and initialized.
  • Ran beamOn for various event counts and primary configurations.
  • Checked output analysis files in both single and multiple run settings.
  • Searched the code to confirm correct calls to G4AnalysisManager’s FillH1 and Write/CloseFile functions.
  • Reviewed Qt3D visualization, which appears normal and shows expected geometry.

Related Information:

  • The code builds and runs fine, but there is simply no data being recorded or histogrammed.
  • Using a completely clean build with no modifications, the executable still operates, and a visual (using Qt3D) can be produced, a beam can be run, and an event can be viewed. But, running livermore.mac fails at /phys/addPhysics emlivermore and would also fail at /cuts/setLowEdge.

Questions:

  • Are there known issues (or required fixes) affecting histogram output in the XrayFluo example when using the Livermore physics list?
  • What are the most likely causes for empty histograms in this example, despite apparently correct event and hit occurrence?
  • Are there debugging strategies or specific analysis manager calls in this example where failures are common (e.g., missed initialization or incorrect FillH1 placement)?

I would greatly appreciate advice on where to look next or suggested modifications.

Thank you in advance!

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