2026 Planned Features

Items in this list are related to developments scheduled for the current year. Fixes, studies and maintenance items, as well as normal testing, Q/A tasks are not mentioned here, as part of routine activity

NOTE: Items marked with (*) may or may not be achieved in 2026.

Configuration & Software Management

  • Modularization of Geant4 Libraries - (1)/(2)
    • Identify libraries for merging or splitting, including optional components
    • Identify and reduce dependencies between components where possible
  • Investigate use of GitLab/Hub CI as a possible replacement for Jenkins - (2)
    • Use for production of binary packages
    • Prepare migration plan for full CI workflows
  • Update documentation, unit testing, and CPU/memory benchmarking of numerical methods and data structures - (2)

Electromagnetic physics & optical processes

  • Infrastructure:
    • Parallel initialisation of EM physics - (1)
    • Restore possibility to use user stopping power tables for ions - (1)
    • EPICS-2017 gamma cross-sections as an alternative in standard models - (2)
  • R&D - G4HepEm and AdePT:
    • Investigate extension to G4HepEm for covering ALICE simulation - (2)
    • Investigate extension to AdePT for including neutron transport - (2)
  • High Energy Physics developments:
    • Model design for X-Ray processes - (2)
    • Analysis of evolution spin polarization - (2)
    • Implementation of thermal photon/inverse Compton - (2)
    • Inclusion of more crystalline materials and orientations in channeling data - (2)
    • Experimental validation and update of G4ChannelingFastSimModel, G4BaierKatkov, G4CoherentPairProduction processes - (2)
    • Implementation of a ML model trained on Particle-in-Cell simulations of laser-driven plasma wakefield acceleration as a particle source- (2)
    • Developments of high-order QED corrections to Bremsstrahlung - (2)
    • Complete the list of next to leading order EM models - (2)
  • Low Energy Physics models:
    • Implementation of ion stopping power in plasma - (1)
    • Developments of plasma physics - (2)
    • Improvements of material handling - (2)
    • Extension of the MicroElec database - (2)
  • Optical photon processes and X-ray physics:
    • Maintenance and optimisation of optical classes - (2)
    • Refactor quasi-scintillation and quasi-Cherenkov processes to support offloading of optical photon transport - (2)
    • Introduction of a model approach into Scintillation and WLS processes - (2)
    • Introduction of a new model for reflection from multilayer surfaces - (2)
  • DNA physics & chemistry
    • Implementation of molecular excitation cross-section model - (1)
    • Update of model interface for O2, N2, CO2 models of ionisation, excitation and elastic scattering - (1)
    • Radio enhancement studies for gold nanoparticle - (2)
    • Extensions to DNA geometries - (2)
    • DNA double-strand break kinetics and repair pathways - (2)
    • Addition and improvement, verification and validation of Geant4-DNA physics models for liquid water (electrons, ions) and other materials - (2)
    • Revision of Geant4-DNA physics constructors - (2)
    • Implementation of cellular oxygen chemistry in Geant4-DNA - (2)
    • Implementation of Li and C cross-sections in Geant4-DNA - (2)
  • Validation & Testing:
    • Validation of three-gamma annihilation of positrons - (2)
    • Verification of the accuracy of the adjoint for space applications - (2)
    • Validation MicroElec model for low-energy protons ionisation - (2)
    • Benchmarking of particle therapy applications - (2)
    • Verification & validation of Geant4-DNA chemistry - (2)

Geometry & Field Transport

  • Use of multi-threading to speed up overlap checking for complex setups - (1)
  • Improvements to parallel geometry initialisation for complex volumes- (1)/(2)
  • Generation of full geometry path for a given volume name - (1)/(2)
  • Improve robustness and performance of selected Geant4 solids - (1)/(2)
  • Introduce strict(er) default accuracy for field propagation - (2)
  • Enhancements to deliver higher GPU navigation performance, and restructure it for consistent behavior across CPU and GPU with a maintainable, portable code base (CUDA/HIP) - (2)
    • Simplification and standardisation of the navigation interface
    • Improvements to GPU navigation performance with new locality-aware accelerator
    • Replacement of recursion with iteration (esp. for Boolean solids)
    • Removal of vector constructs to simplify code and improve scalar performance
    • Addition of a portability layer and refactoring of device code to POD + explicit dispatch (no device virtuals)

Hadronic Physics

  • String Models
    • Analysis of Lambda hyperon production in nucleus-nucleus interactions based on NA61/SHINE measurements - (1)/(2)
    • Analysis of Au+Au interactions with BES (RHIC) data - (1)/(2)
    • Improvements to simulation of deuteron properties - (1)/(2)
    • In QGS model, inclusion of finite energy corrections to the eikonal approximation - (1)/(2)
    • Improvement of light anti-nucleus - nucleus cross-sections at low energies using ALICE data - (1)/(2)
    • Improvement to the probability of production of charmed particles for soft hadron-proton and proton-nucleus interactions using experimental data - (1)/(2)
    • Improvement of the kinematical properties of charmed particles produced in hadron-proton interactions in QGS and FTF models using experimental data - (1)/(2)
    • Model parameter studies of BERT model - (1)/(2)
    • Investigation of open issue with longitudinal pion showers in ATLAS FCAL - (1)/(2)
    • Maintenance and improvement of the hadronic framework; code improvements of FTF and QGS models - (1)/(2)
  • Intra-nuclear Cascade models
    • Code review and maintenance in Bertini-like (BERT) and Binary (BIC) models - (1)/(2)
    • Extension for antideuteron in Liege (INCLXX) model - (1)/(2)
    • Optimisation of parameters and propagation of uncertainties in INCLXX - (1)/(2)
  • Precompound/de-excitation Models
    • Tuning of parameters in de-excitation, based on experimental data - (1)/(2)
    • Development of a new multi-fragmentation model - (1)/(2)
    • Addition of more fission modes in ABLA++ to improve the description of mass and charge distributions of fission fragments at low excitation energies - (1)/(2)
    • Optimisation of parameters in ABLA++ - (1)/(2)
  • Radioactive Decay model
    • Implementation of user-defined spectrum for beta and beta+ decays - (1)/(2)
  • High Precision (HP) Models
    • Implement the use of pre-Doppler broaden cross-section database at a given temperature; implementation of the algorithm that allows to do that at the beginning of a Geant4 simulation - (1)/(2)
    • Translation of new nuclear data library releases from the ENDF-6 format to the G4NDL format, and verification - (1)/(2)
    • Refinements to the integration of the NuDEX model into Geant4, and expand its usage (not only in neutron capture reactions) - (1)/(2)
    • Improvement and speed-up of Particle-HP code - (1)/(2)
  • Low Energy Neutron Data Model
    • Updates to LEND and GIDI - (1)/(2)
  • Hadronic Elastic Models
    • Review of the pion elastic scattering model - (1)/(2)
    • Improvements to elastic scattering of p+d, d+d, d+A, and other light nuclei at high energies using Glauber approximation - (1)/(2)
  • Other models
    • Development and validation of gamma/lepton/neutrino - nuclear physics - (1)/(2)
    • Maintenance of the interface to FLUKA.CERN for hadron-nucleus inelastic cross-sections and final-state interactions - (1)/(2)
    • Use of Pythia8 as an external generator: application for LDMX experiment - (1)/(2)
    • Consolidation of the charge exchange of pions and kaons - (1)/(2)
    • Explore the possibility of emulating BLOB or a portion of it with DL and of a differentiable pipeline to optimize QMD and LIQMD free parameters - (1)/(2)
    • Updates to the QMD model, investigating the nucleon-nucleus inelastic cross-section; preparation of a new version of QMD based on a relativistic nuclear model - (1)/(2)
    • Muonic atoms developments - (1)/(2)
    • Implementation of the AMS (Adaptive Multilevel Splitting) variance reduction technique - (1)/(2)
  • Validation & Testing
    • Creation of tests for validating the production of charmed particles in hadron-proton and proton-nucleus interactions - (1)/(2)
    • Validation of the alternative FermiBreakUp and GEM models - (1)/(2)
    • Coverage extendsion of hadronic tests for calorimeter test-beams and low-energy neutron tests - (1)/(2)
    • Hadronic validation using thin-target data and tests relevant to Fermilab experiments - (1)/(2)
    • Study of the sensitivity of the MC predictions to the variations of various parameters and development of needed infrastructure - (1)/(2)
    • Validation and support of hadron-therapy applications - (1)/(2)
  • Hadronic Datasets
    • Refinements to Hadronic Datasets G4ENSDFSTATE, PhotonEvaporation, RadioactiveDecay - (1)/(2)
    • Update of G4PARTICLEXS based on room-temperature cross-sections of Particle-HP. Optimisation of accuracy, computational performance and memory footprint - (1)/(2)

Materials, Generic Processes and Parameterisations

  • Fast Simulation
    • Revision and improments of GFlash models - (1)/(2)
    • Developments in AI-based fast simulation models - (1)/(2)
      • Introduction of optional and GPU-enabled tests for ML inference
      • Implementation of per-event batching
      • Development of high-granularity CaloDiT-2 (in view of CMS)
      • Studies of step-level shower data for preparation of point-cloud representations
  • Biasing
    • Investigate overlap between generic and geometrical biasing - (1)/(2)
    • Prototyping of DXTRAN-like functionality - (1)/(2)
    • Biasing of charged particle interaction occurrence - (1)/(2)
    • Extend generic biasing scheme for at rest case - (1)/(2)
    • Design document for Implicit capture & implementation - (1)/(2)
  • Materials
    • Code improvements - (1)/(2)
  • Scoring
    • Refinements to parallel world scoring - (1)/(2)

Particles & Tracking

  • Update of particle properties to latest 2026 PDG data - (1)/(2)
  • Performance tests and improvements - (1)/(2)
  • Polishing up code readability and documentation - (1)/(2)
  • Re-design and implementation of G4ForceConditions - (1)/(2)

Persistency & Analysis

  • Regular maintenance & extensions to GDML and analysis classes- (1)/(2)
  • !!! 2026 ITEMS TO BE PROVIDED !!!

Physics Lists

  • Review of physics lists code - (1)/(2)
  • Recommendation/documentation of physics-lists for specific use cases - (1)/(2)
  • Maintenance and upgrade of the PenelopeEM physics constructor - (1)/(2)
  • Review organisation of library structure to allow for optional libraries build - (1)/(2)
  • Maintenance of the alternative/extensible physics list factory relevant to the Intensify-Frontier - (1)/(2)

Physics Validation and Tools

  • Inclusion of detailed vs fast simulation comparison/validation tests into geant-val - (1)/(2)
  • !!! 2026 ITEMS TO BE PROVIDED !!!

Run, Event, Detector Response & Scoring

  • Split initialization from event processing and create its dedicated task - (1)/(2)
    • Enable the use of all available threads for initialization regardless of number of events to be processed
  • Review of scoring in parallel world and validation of all primitive scorers - (1)/(2)
  • Addition of drawing methods to probe scores - (2)
  • Interface to HepMC3 with a new example - (2)
  • Enhancements to material scanner utility and revision of ray-tracer - (2)

Visualisation and Graphics Representations

  • Management:
    • Implementation of similar interactive behaviours across all interactive viewers - (2)/(*)
    • Implementation of generic “packaging” of data for optimal usage on GPUs - (2)/(*)
    • Gaussian splat rendering - (2)/(*)
  • Qt GUI:
    • Reimplementation of usage of .ui file - (*)
  • TSG driver:
    • Optimisation of GL-3.2 - (1)
    • Picking and pop-up menu - (2)/(*)
    • 2-D plots - (*)
  • Ray Tracer:
    • Change default window to 1000x1000 - (1)
    • Refinements to shadow and mirror drawing - (2)
  • Vtk driver:
    • Implementation of picking - (1)
    • Review all OGL features for availability in VTK driver - (1)/(2)
    • Solid cylinder for trajectory (option) to enable usage of exported data in a wide range of 3D applications - (1)/(2)
    • Option for sphere/circle and cylinder/line - (1)/(2)
    • Release of USD interface - (1)/(2)
    • GLTF interface - (1)/(2)
  • Open Inventor:
    • Improved use/install of Coin library - (1)
    • Evolution for Qt6 compatibility - (1)/(2)
    • Work on reference path to move through the geometry - (*)
  • Other drivers:
    • gMocren: design and implementation to get some attributes for drawing detectors - (1)/(2)

Advanced Examples

  • Plasmid DNA damage with MolecularDNA example - (2)
  • !!! 2026 ITEMS TO BE PROVIDED !!!

Novice & Extended Examples

  • Add flexibility for changing geometry between runs to GFlashA - (1)/(2)
  • New gflash example for sampling calorimeter - (1)/(2)
  • New example demonstrating Julia bindings - (1)/(2)
  • New example with ion Geant4-DNA cross-sections - (1)/(2)
  • New example to examine all primitive scorers - (1)/(2)
  • New example interfacing with HepMC3 - (1)/(2)
  • Continue application of coding guidelines - (1)/(2)
  • Implementation of HEP related examples/tests for AdePT for inclusion in nightly/CI - (2)
  • New example to illustrate the use of the Inverse Compton Scattering event generator - (2)
  • Reverse MC example coupling Reverse and Biasing framework (for force interaction in target volume) - (2)
  • Improvements to the Par04 example brought from the experience of implementation for the experiments - (2)
  • Medical/DNA:
    • Management of different geometries (shape, dimensions, materials) in icsd example - (1)/(2)
    • Incorporation of the calculation of (weighted) energy imparted to the site per proton collision in microtrack example - (1)/(2)
    • Improvements to molcounters example - (1)/(2)
    • Extension to neuron example, to continue studies of DNA damage using intermediate-Z ions (He, Li, N, Ne) and validation of the new detailed chromatin/chromosome geometries - (1)/(2)
    • Update of scavenger example for different time-step models (IRT-syn, SBS) - (1)/(2)
    • Code refactoring in wholeNuclearDNA example - (1)/(2)
    • Update to UHDR example for multipe pulse, benchmarking - (1)/(2)

Deadlines

  • First semester - 26 June 2026
  • Second semester - 4 December 2026