G4Horus

An implementation of the HORUS High-Purity Germanium (HPGe) γ-ray spectrometer and associated equipment in Geant4.

Overview

The main goal of this project is to provide an accurate, easy-to-use efficiency simulation for the HORUS setup at the Institute for Nuclear Physics, University of Cologne.

Components:

• Geometries
  • Target Chambers
    • Astro Target Chamber
    • Astro Target Chamber V2
    • SONIC
    • SONIC V3
    • SONIC V3 ΔEE
  • Setups (HPGe Arrays with positions for HPGe Detectors)
    • HORUS (14)
    • Cologne Clover Counting Setup (2)
  • Detectors
    • High-Purity Germanium (HPGe)*
      • Coaxial (default)
      • Clover
      • Encapsulated Hexagonal
    • Bismuth Germanate (BGO) anti-Compton shields
    • (WIP) Passivated Implanted Planar Silicon (PIPS)
  • Auxiliary equipment
    • γ-Filter-Disks
    • (NYI) Passive γ-Supershields
• Actions
  • Event Generators
    • Particle Gun
    • (WIP) Scattering Gun
    • (NYI) Coincidence Gun
  • Output Formats
    • ROOT Histograms
    • ROOT Ntuples (not recommended)
    • SOCOv2 Events
  • Evaluation
    • Visualization Mode
    • Batch processing Mode
    • Automated efficiency evaluation

*) Note that each HPGe detector has unique properties, stored in the DetectorLibrary, and is referenced by its manufactured ID.

Getting Started

Dependencies

• A not horribly outdated C++ build environment (cmake >= 3.11, gcc with C++11 support)
• Geant4 >= 10.5 (make sure the proper environment variables are set, see example in G4Horus.sh)
• Assimp to load binary stl files. Should be available in your package manager. Note: CADMesh is bundled and does not need to be installed separately anymore.

Installation

git clone https://gitlab.ikp.uni-koeln.de/jmayer/g4horus.git
cd g4horus
./G4Horus.sh

The project should compile and open a visual interface with a default view should open.

Quick Simulation

• Run ./G4Batch.sh scripts/doit.mac or other macro files to run the actual simulation.
• Use ./efficiency.sh to automatically extract efficiencies from the simulated data.

Constructing the Setup

The experimental setup is assembled in src/DetectorConstruction.cc. Change the target chamber, detectors, and sensitive volumes here. Use ./G4Horus.sh to check your setup.

Example for equipping HORUS with detectors:

auto horus = new Horus(worldLV);
// ID, Position, Distance (to endcap or filters on endcap), Filters
// BGO Type, Position, Distance (to BGO or filters on bgo), BGO-Filters
horus->PlaceDetector("73954", "Ge00", 20. * cm);
horus->PlaceDetector(BGO::tSMALLNOSE, "BGO00", 10. * cm, {{"G4_Cu", 2. * mm}});

and the sensitive volumes (WIP):

extern const std::vector<std::string> detectors = {"Ge00", "BGO00"};

Note that without setting the sensitive detector, no output will be recorded.

The output type is set in G4Batch.sh, e.g. -k hist for histograms and -k soco for SOCOv2 events.