Low Energy Electromagnetic Physics - Overview

Geant4 10.4

  • Version 7.3 of the G4EMLOW dataset is required
  • Livermore: update of photoelectric model from EPICS2014.
  • Atomic deexcitation: updated set of shell ionisation cross sections for PIXE from calculations by M. Reis et al..
  • Geant4-DNA: new electron cross section models for liquid water from the CPA100 Monte Carlo code and for DNA materials from experimental measurements.
  • Geant4-DNA: new G4DNAElectronSolvation process for the handling of sub-excitation electrons in all constructors.
  • Geant4-DNA: update of G4EmDNAPhysicsActivator for DNA models configuration per particle type (see dnaphysics example).
  • Geant4-DNA: new examples: chem4 (radiochemical yields with ROOT interface), mfp (mean free path), microyz (microdosimetry), neuron (network of neuron cells), slowing (slowing down spectra), spower (stopping power).
  • Geant4-DNA: examples: addition of all Geant4-DNA constructors.
  • Geant4-DNA: addition of dna.mac to TestEm5 for the tagging of deexcitation products.
  • Geant4-DNA: new publications - see this link.
  • More details in the Release Notes and on the Geant4-DNA site.

Geant4 10.3

  • Livermore, Penelope: sampling of lateral displacement for the Urban model has been updated in Option3, Option4, Livermore and Penelope physics configurations. Due to that, the Urban model predictions become close to predictions of Goudsmit-Saunderson and Wentzel-VI models.
  • MicroElec models: acceleration of discrete elastic scattering model.
  • Atomic deexcitation: fluorescence and Auger cascades are activated by default in all Geant4-DNA physics constructors.
  • Geant4-DNA: G4EmDNAPhysicsActivator is a new class for DNA models configuration per particle type (replacing G4EmModelActivator for DNA models).
  • Geant4-DNA: new example for the simulation of radiochemical yields.
  • Geant4-DNA: new publications - see this link.
  • More details in the Release Notes.

Geant4 10.2

    • Monash U.: new Monash Compton model G4LowEPPolarizedComptonModel including polarization.
    • Atomic deexcitation: possibility to simulate Auger cascades.
    • Geant4-DNA: new models for electrons: G4DNAEmfietzoglouExcitationModel, G4DNAEmfietzoglouIonisationModel and G4DNAUeharaScreenedRutherfordElasticModel.
    • Geant4-DNA: new model G4DNAIonElasticModel for nuclear scattering of ions.
    • Geant4-DNA: update of physics constructors.
    • Geant4-DNA: added new examples to $G4INSTALL/examples/extended/medical/dna.
    • More details in the Release Notes.

    Geant4 10.1

      • Livermore: low-energy cross-section for water has been added for the low-energy Livermore photoelectric model.
      • Atomic deexcitation: a new User Interface command to disable production thresholds in atomic deexcitation has been introduced: "/process/em/deexcitationIgnoreCut true/false".
      • Atomic deexcitation: an alternative set of data files for the simulation of atomic fluorescence lines is provided.
      • Geant4-DNA: extended G4DNARuddIonisationExtendedModel for B, Be, Li and Si ions. 
      • Geant4-DNA: G4DNAIonisation and G4DNARuddIonisationExtendedModel have been updated for G4GenericIon usage.
      • Geant4-DNA: a new model class G4LowEWentzelVIModel is introduced for low-energy electron elastic scattering. 
      • Geant4-DNA: classes for the simulation of water radiolysis have been introduced. 
      • Geant4-DNA: all examples have been moved to the "extended/medical/dna" category. 
      • More details in the Release Notes.

      Geant4 10

        • Upgrade of low energy models to MT : Livermore gamma models and bremsstrahlung, Penelope
        • G4MuElec* processes and models renamed as G4MicroElec* processes and models
        • A new advanced example is available for microelectronics simulations in Silicon: microelectronics.
        • A new advanced example is available for the modeling of cellular nuclei including DNA geometrical model: dnageometry.

        Geant4 10 BETA

        • Beta MT migration of dnaphysics advanced example
        • Beta MT migration of microdosimetry advanced example
        • Improvement of computing speed of Geant4-DNA Born ionisation model 

        Geant4 9.6+P02

          • New constructor for the most accurate models available in standard and low energy categories (G4EmStandardPhysics_option4)
          • Physics constructor (G4EMLivermoreMUPhysics) renamed as (G4EmLowEPPhysics)
          • Improvement of Livermore gamma models, including fix to atomic de-excitation in the Livermore photoelectric model in release Geant4 9.6
          • Fix of bug affecting the G4EmLivermorePhysics constructor in releases Geant4 9.6 and 9.6P01

          Geant4 9.6 BETA

            • New processes (G4MuElecElastic, G4MuElecInelastic) for microdosimetry in Si for electrons, protons and ions and models (G4MuElecElasticModel, G4MuElecInelasticModel)
            • New Compton scattering model (G4MUComptonModel) along with specific Physics constructor (G4EMLivermoreMUPhysics) 
            • Removed dependency on obsolete G4AtomicDeexcitation in Penelope
            • Simplified usage of UI atomic de-excitation commands

            Geant4 9.5

              • Added new Bremsstrahlung model based on Penelope v2008
              • Updated methods and UI commands for atomic deexcitation
              • Added ionization cross sections classes for PIXE for protons and alphas according to A.Taborda, M. Reis et al.
              • Removed all G4LowEnergy* classes
              • Added prototype software for radiation chemistry modelling in Geant4-DNA
              • Extension of Geant4-DNA ionization to HZEs

              Geant4 9.5 BETA

                • Added new web page on migration of obsolete low energy electromagnetic classes
                • Migrated electromagnetic Standard, Low Energy and Geant4-DNA physics builders to the new approach which does not require physical process numbering
                • G4EmLivermorePhysics, G4EmLivermorePolarizedPhysics, G4EmPenelopePhysics use UrbanMscModel95 for multiple scattering for e+-
                • Made all Penelope version 2008 models the default Penelope models
                • New atomic de-excitation interface available to Standard, Livermore (photoelectric, Compton, ionisation), Penelope (photoelectric, Compton) and Geant4-DNA (ionisation) physics. See more details at this page.
                • New module dedicated to Geant4-DNA developments
                • New dnaphysics advanced example exercising Geant4-DNA processes, including variable density material definition
                • Upgraded the microdosimetry advanced example exercising multi-scale discrete/non-discrete combination of Geant4-DNA and Geant4 electromagetic processes

                Geant4 9.4

                  • Photon Livermore models: first implementation of pair production in the electric field of the electron. The G4BoldyshevTripletModel should be used in conjunction with the G4LivermoreNuclearGammaConversionModel model (using G4MultiModel) in order not to account twice for the pair production cross section in the electron field.
                  • Electron Livermore models: G4LivermoreIonisationModel is able to generate fluorescence along the step.
                  • Penelope models: added four new models (gamma ray models: Compton, GammaConversion, PhotoElectric and Rayleigh). Upgrades of Penelope from version 2001 to version 2008, named as G4Penelope08xxxxModel. To be considered as beta.
                  • For all low energy EM models: no customized production cuts are allowed anymore for fluorescence/Auger. Main cuts from the G4ProductionCutsTable are always used, for consistency.
                  • Geant4-DNA (in liquid water)
                    • New process and model classes for electron attachment and vibrational excitation.
                    • New electronic excitation model for electrons.
                    • Extended very low energy coverage of Champion's electron elastic scattering.
                    • New excitation model for neutral hydrogen.
                    • Preliminary new ionization models for C, N, O and Fe. To be considered as beta.
                    • Multi-scale combination of Geant4-DNA discrete processes with Standard or low energy EM physics processes adopting the unified software approach of both EM physics sub-categories (see the microdosimetry advanced example for illustration).

                  Geant4 9.4 BETA

                    • Added four new models (gamma ray models Compton, GammaConversion, PhotoElectric, Rayleigh), corresponding to upgrade of G4Penelope from version 2001 to version 2008.
                    • Added new prototype excitation model for electrons in G4DNABornExcitationModel. 
                    • New PIXE developments: the G4ecpssrKCrossSection and G4ecpssrLiCrossSection classes substitute the G4ecpssrCrossSection class. New interfaces G4empCrossSection and G4teoCrossSection.

                    Geant4 9.3

                        • Full release of new software design for Low-Energy electromagnetic Physics models (see more from this link). Users are invited to update their simulation application(s) accordingly (see link).
                        • Computing performance of low energy models has been significantly improved thanks to new implementations for data loading and interpolation methods, transparent to the user's application.
                        • New Livermore models (G4LivermorePolarizedPhotoElectricModel and G4LivermorePolarizedGammaConversionModel) are available for the simulation of polarized photon interactions
                        • ICRU'73 ion model : the upper energy limit of ICRU'73 stopping power tables was extended to 1 GeV/nucleon (compared to 10 MeV/nucleon in the previous release). Revised tables were included for G4_WATER, G4_WATER_VAPOR, G4_Cu, G4_NYLON-6-6 (all tables provided by P. Sigmund/Univ. of Southern Denmark).
                        • Geant4-DNA Physics
                          • Energy range coverage of several Geant4-DNA Physics models has been extended: electron elastic Champion's model from 8.23 eV up to 10 MeV; electron ionization Born's model from 11 eV up to 1 MeV; proton excitation Born's model up to 100 MeV; proton ionization Born's model up to 100 MeV.
                          • Geant4-DNA models are valid for liquid water only and use now the G4_WATER NIST material as liquid water material definition. Users should define liquid water as G4_WATER only in their application(s) if they want to use Geant4-DNA models.
                        • Data set: G4EMLOW version 6.9 is required.

                        Geant4 9.3 BETA

                        • The new software is now available in the Geant4 9.3 BETA release and adopts a common software design with the design proposed by the Standard EM working group. This allows smooth, flawless integration with established Standard EM processes and models, giving the user the possibility of an optimised choice of best Physics models, now fully collaborating over an even wider energy range. Livermore, Penelope and Geant4-DNA models are concerned.
                        • With this new design, new Physics builders are available. In particular, Livermore and Penelope Physics builders allow a combination of Low Energy EM models with Standard EM models (see link).
                        • new stopping power model for ions based on ICRU73 data tables is now fully available and has been developed in full collaboration with the Standard EM WG.
                        • An alternative electron elastic scattering model proposed by C. Champion is available in Geant4-DNA processes (see link).
                        • More details can be accessed from this link.

                        July 2008: new website for the Geant4 Low-Energy WG activities

                        The new web site LowEnergyElectromagneticPhysicsWorkingGroup describes up-to-date on-going developments.

                        May 2008: new Geant4 Low-Energy WG coordination and regulation

                        Following the new Geant4 collaboration agreement (see link), and after a transition period, the working group members elected a new coordinator and two new representatives to the Geant4 steering board, in full collaboration with the Geant4 Standard Electromagnetic Physics Working Group. The positions are now held by: 
                        • Geant4 Low-Energy WG coordinator: Sébastien Incerti (CNRS/IN2P3/CENBG, Bordeaux, France) 
                        • Geant4 Steering Board representatives : Giacomo Cuttone (INFN/LNS, Catania, Italy) who is also deputy coordinator, and Paul Guèye (Hampton Univ., Hampton, VA, USA)