Given the toolkit nature of Geant4, a choice of physics processes is
available. The choices offer either different detail of physics modeling or
different physics modeling descriptions. It is the choice of the user to decide
how much detail in the physics modeling is needed, weighing the detail against
cpu performance. A user can construct his own physics list, or use one of the
physics lists offered below, or modify any of the offered physics lists.
Please see the detailed description for a
full description of all reference physics lists including our current understanding of
The reference physics lists are part of the Geant4 source code and are
distributed as an integral part of Geant4 from the
Geant4 download area.
Physics lists include those originally named 'educated guess physics lists'.
Nearly all these lists are suitable for all primary particles and for a wide range of energies.
There are four families of lists:
All of the lists in the first three families share components to attach certain types of processes to
groups of particles. The classes of components are:
- LHEP or parameterised modeling of hadronic interactions.
- QGS, or lists based on a modeling using Quark Gluon String model for high
energy hadronic interactions of protons, neutrons, pions, and Kaons.
- FTF, or lists based on a modeling using the FTF model for high energy
hadronic interactions of protons, neutrons, pions, and Kaons; FTF is FRITIOF like
- several more specialised lists.
- electromagnetic interactions for
all particles and electromagnetic processes for leptons and gammas.
settings are offered
- the default setting using standard parameters tuned for best
- using parameters optimised for better CPU performance at the cost slightly less
precise physics. This is identified in physics lists by the extension
- a set of experimental parameters, used by physics lists with the extension
- Inelastic interactions for hadrons
- Elastic scattering of hadrons off nuclei
- Capture at rest for negative charged hadrons and muons
- Decay of unstable particles in flight and at rest
- specialised treatment of low energy neutrons ( < 20MeV)
Physics Lists in Geant4 examples
Other Physics Lists