Electromagnetic Physics


The electromagnetic (EM) physics working group develops and maintains Geant4 sub-packages for simulation of electromagnetic interactions of charged particles, gammas and optical photons. The validity range of models is from threshold to 10 PeV. The "standard" physics approaches are optimal for high and medium energy applications. The "low-energy" sub-library is developed for low-energy applications. The group is maintaining also components for reference Physics Lists and a number of extended examples.


  • John Apostolakis (CERN, Geneva, Switzerland) - design assessment, performance
  • Alexander Bagulya (Lebedev, Physics Institute, Moscow, Russia) - validation, ionisation
  • Denis Bernard (IN2P3/LLR, Paris, France) - gamma conversion
  • Alexey Bogdanov (MEPhI, Moscow, Russia) - muons
  • Marie-Claude Bordage (CNRS, France) - Geant4-DNA
  • Jeremy Brown (Technical University, Delft, The Netherlands)
  • Igor Bulyzhenkov (MIPT, Moscow, Russia) - high energy processes
  • Marilena Bandieramonte (CERN, Geneva, Switzerland) - photoeffect, vector prototype
  • Helmut Burkhardt (CERN, Geneva, Switzerland) - rare processes, applications for CLIC
  • Gerardo Depaola (FAMAF, Argentina) - polarized processes
  • Paolo Dondero (Swhard, Genova, Italy) - validation
  • Sabine Elles (LAPP, Annecy, France) - validation
  • Bruce Faddegon (UCSF, CA, USA) - medical applications
  • Ziad Francis (St Joseph University, Lebanon)
  • Vladimir Grichine (CERN; Lebedev Physics Institute, Moscow, Russia) - xrays, gaseous detectors
  • Susanna Guatelli (Wollongong University, Australia) - medical application
  • Paul Gueye (Hampton University, VA, USA)
  • Peter Gumplinger (TRIUMF, Vancouver, Canada) - optical, xrays
  • Sébastien Incerti (CNRS, France) (deputy coordinator, Geant4-DNA)
  • Vladimir Ivanchenko (CERN; RAS,  Tomsk State University Russia) - coordinator, SB member
  • Omrane Kadri (King Saud University, Saudi Arabia) - multiple scattering, validation
  • Mathieu Karamitros (Pessac, France) - Geant4-DNA
  • Ioanna Kyriakou (Ioannina University, Greece) - low-energy models
  • Nathanael Lampe (Melbourne, Australia) Geant4-DNA
  • Se Byeong Lee (NCC, Korea) - medical applications
  • Francesco Longo (INFN/Trieste, Trieste, Italy) - space applications
  • Michel Maire (LAPP, Annecy, France) - deputy
  • Alfonso Mantero (Swhard, Genova, Italy) - validation
  • Mihaly Novak (CERN, Geneva, Switzerland) - multiple scattering models
  • Luciano Pandola (INFN/LNS, Catania, Italy) (deputy coordinator) - Penelope models
  • Ivan Petrovic (Vinca Institute, Belgrade, Serbia)
  • Mélanie Raine (CEA, Paris, France)
  • Jose Ramos-Mendez (UCSF, CA, USA)
  • Miguel Reis (ITN, Portugal)
  • Aleksandra Ristic-Fira (Vinca Institute, Belgrade, Serbia)
  • Giorgio Russo (INFN/LNS, Italy)
  • Dousatsu Sakata (Wollongong University, Australia)
  • Giovanni Santin (ESA/ESTEC, The Netherlands)
  • Daren Sawkey (Varian Medical Systems, Palo Alto, USA) - validation, electrons, deputy, SB member
  • Igor Semeniouk (IN2P3/LLR, Paris, France) - gamma conversion
  • Jae Ik Shin (NCC, Korea)
  • Wook Geun Shin (Bordeaux University, France)
  • Toshiyuki Toshito (Health and Welfare Bureau, Nagoya, Japan) - ions, validation
  • Hoang Tran (CEA, France) - Geant4-DNA
  • Laszlo Urban (G4AI, Budapest, Hungary) - standard processes
  • Carmen Villagrasa (IRSN, Paris, France) - Geant4-DNA
  • Tomohiro Yamashita (HIBMC, Hyogo, Japan) - validation

Suspended Geant4 and Standard Electromagnetic Physics group members

Collaborators developing polarized processes (not Geant4 members)

Collaborators developing Coulomb scattering models (not Geant4 members)

Sub-packages and processes

Sub-directory Process or user interface SubType Comment
electromagnetic/highenergy G4AnnihiToMuPair 4 positron annihilation to muon pair
electromagnetic/highenergy G4GammaConversionToMuons 5 gamma conversion to muon pair
electromagnetic/highenergy G4eeToHadrons 4 positron annihilation to hadrons
electromagnetic/highenergy G4hhIonisation 2 heavy particle ionisation
electromagnetic/highenergy G4mplIonisation 2 classical magnetic monopole ionisation
electromagnetic/muons G4MuBremsstrahlung 3 muon bremsstrahlung
electromagnetic/muons G4MuIonisation 2 muon ionisation
electromagnetic/muons G4MuMultipleScattering 1 multiple scattering for muons
electromagnetic/muons G4MuPairProduction 8 e+e- pair production by muon
electromagnetic/muons G4ePairProduction 8 e+e- pair production by e+,e-
electromagnetic/polarisation G4PolarizedCompton 6 Compton scattering with circular polarization
electromagnetic/polarisation G4PolarizedGammaConversion 5 conversion of circular polarized gamma
electromagnetic/polarisation G4PolarizedPhotoElectricEffect 7 photo-electric effect for circular polarized gamma
electromagnetic/polarisation G4ePolarizedBremsstrahlung 3 bremsstrahlung of circular polarized e+ and e-
electromagnetic/polarisation G4ePolarizedIonisation 2 ionisation of circular polarized e+ and e-
electromagnetic/polarisation G4eplusPolarizedAnnihilation 4 annihilation of circular polarized positrons
electromagnetic/standard G4ComptonScattering 6 Compton scattering process
electromagnetic/standard G4CoulombScattering 1 single Coulomb scattering
electromagnetic/standard G4GammaConversion 5 gamma conversion to e+e- pair
electromagnetic/standard G4NuclearStopping 8 nuclear stopping of ions
electromagnetic/standard G4PhotoElectricEffect 7 photo-electric effect
electromagnetic/standard G4PolarizedComptonScattering 6 Compton scattering of linear polarized gamma
electromagnetic/standard G4eBremsstrahlung 3 electron and positron bremsstrahlung
electromagnetic/standard G4eIonisation 2 electron and positron ionisation
electromagnetic/standard G4eMultipleScattering 10 electron and positron multiple scattering
electromagnetic/standard G4ionIonisation 2 ionisation of ions with charge +2 and more
electromagnetic/standard G4hIonisation 2 ionisation of hadrons
electromagnetic/standard G4hMultipleScattering 10 multiple scattering of heavy changed particles
electromagnetic/xrays G4Cerenkov 21 Cerenkov radiation
electromagnetic/xrays G4Scintillation 22 scintillation process
electromagnetic/xrays G4SynchrotronRadiation 23 classical synchrotron radiation
electromagnetic/xrays G4SynchrotronRadiationInMat 23 synchrotron radiation in media
electromagnetic/xrays G4TransitionRadiation 24 transition radiation process
optical G4OpAbsorption 31 absorption of optical photons
optical G4OpBoundaryProcess 32 general boundary process for optical photons
optical G4OpRayleigh 33 Rayleigh scattering of optical photons
examples/extended/electromagnetic/TestEm7 G4ScreenedNuclearRecoil 1 single scattering for ions

Helper classes

Sub-directory Process or user interface Comment
electromagnetic/muons G4EnergyLossForExtrapolator Class for computation of energy loss and fluctuations by external codes
electromagnetic/utils G4EmCalculator interface to dE/dx and cross sections
electromagnetic/utils G4EmConfigurator adding models to Physics List
electromagnetic/utils G4NIELCalculator Computation of NIEL energy loss at a step
electromagnetic/utils G4EmParameters C++ interface to EM options (since Geant4 10.1)
electromagnetic/utils G4EmSaturation Computation of energy loss saturation (Birks effect)
materials G4NistManager Access to Geaant4 NIST DB and atomic properties


User support

The group is providing and maintaining extended examples:

  • electromagnetic;
  • exoticphysics;
  • medical;
  • optical;
  • polarisation.

We are suggesting our users to visit the forum "Physics Processes", that is the best way to exchange information.