Introduction to GEANT4
From UCL HEP PBT Wiki
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== <span style="color:#000080"> Physics processes </span> == | == <span style="color:#000080"> Physics processes </span> == | ||
| + | <span style="color:#ff0000"> G4VUserPhysicsList </span> is a mandatory user class. It has three methods: | ||
| + | |||
| + | * ConstructParticles(): define all necessary particles; | ||
| + | * ConstructProcesses(): define all necessary processes and assign them to proper particles; | ||
| + | * SetCuts(): define production thresholds (in terms of range); | ||
| + | |||
| + | GEANT4 provides a variety of physics processes of particle interactions with matter. There are seven categories of processes provided by GEANT4: | ||
| + | |||
| + | # electromagnetic | ||
| + | ** standard | ||
| + | ** low Energy (Livermore Library / Penelope) | ||
| + | # hadronic | ||
| + | # decay | ||
| + | # photolepton-hadron | ||
| + | # optical | ||
| + | # parameterization | ||
| + | # transportation | ||
| + | |||
| + | This example shows how to define your own class from the G4VUserPhysicsList base class. | ||
| + | |||
| + | |||
| + | <span style="color:#800000"> MyPhysicsList :: MyPhysicsList(): G4VUserPhysicsList() </span> | ||
| + | <span style="color:#800000"> { </span> | ||
| + | <span style="color:#800000"> //Define production thresholds </span> | ||
| + | <span style="color:#800000"> defaultCutValue = 1.0*cm; </span> | ||
| + | <span style="color:#800000"> } </span> | ||
| + | <span style="color:#800000"> void MyPhysicsList :: ConstructParticles() </span> | ||
| + | <span style="color:#800000"> { </span> | ||
| + | <span style="color:#800000"> //Define the particles </span> | ||
| + | <span style="color:#800000"> G4Electron::ElectronDefinition(); </span> | ||
| + | <span style="color:#800000"> G4Positron::PositronDefinition(); </span> | ||
| + | <span style="color:#800000"> G4Gamma::GammaDefinition(); </span> | ||
| + | <span style="color:#800000"> } </span> | ||
| + | <span style="color:#800000"> void MyPhysicsList :: SetCuts() </span> | ||
| + | <span style="color:#800000"> { </span> | ||
| + | <span style="color:#800000"> //Set the production threshold </span> | ||
| + | <span style="color:#800000"> SetCutsWithDefault(); </span> | ||
| + | <span style="color:#800000"> } </span> | ||
== <span style="color:#000080"> Generate primary particles </span> == | == <span style="color:#000080"> Generate primary particles </span> == | ||
