Today's exercises cover the following items:
The Geant4 application example, which is presented on the main page, serves again as the basis of the exercises. Do not use the example with your modifications from yesterday, but download again the original tar-ball (you may find the instructions below).
The exercises of today include the modification and/or extension of the following classes:
Please note, that some exercises rely on the successful completion of previous exercises, i.e. previously introduced functionalities might be used at a later stage. These mandatory exercises are marked with a star next to the exercise number (*). If you don't manage to complete them by your own, try to understand the provided solutions and introduce the requested functionalites into your example.
Exercise 3-1
Exercise 3-2*
You can find here the header file for a new physics constructor class (PhysicsEMElectronEEDL), which should construct electromagnetic (EM) processes of electrons. Implement the method ConstructProcess (in a new file PhysicsEMElectronEEDL.cc), in order that it instantiates the classes representing:
Exercise 3-3
Integrate the physics constructor class of the previous exercise into the example application: A user should be able to activate via a macro command the EM physics for electrons defined in PhysicsEMElectronEEDL as an alternative option to the penelope physics (PhysicsEMElectronPenelope):
Exercise 3-4
The physics constructor class PhysicsEMHadronIonLowEnergy instantiates electromagnetic physics processes for charged hadrons and ions. The included processes are:
Exercise 3-5
The processes to describe inelastic interactions of protons and neutrons are included in the
G4VPhysicsConstructor class called PhysicsHIProtonNeutron.cc.
Inelastic interactions of protons are described by the Binary Cascade model (G4BinaryCascade) between 0 and 10 GeV.
For this exercise:
Exercise 3-6
During the simulation (e.g. when primaries are high-energy protons or neutrons) you may produce secondary pions (or you may take pions as primaries). For pions the decay process is active, so they may decay and produce muons. In the physics list provided in the example, muons are defined as particles, but no processes are registered for them. It means that they would be tracked by Geant4 without undergoing any interaction.
The purpose of this exercise is to create a new physics constructor class (as done for exercise 3-2) which implements electromagnetic processes for muons in its ConstructProcess() method. The header file for this class is here.
The processes to be registered to the muon ProcessManager are: G4MuMultipleScattering, G4MuIonisation, G4MuBremsstrahlung and G4MuPairProduction. The first three processes (multiple scattering, ionisation and bremsstrahlung) have AlongStep() and PostStep() action, while muon pair production has only PostStep() (namely it is a discrete process).
Notice: you have to take into account both negative and positive muons (G4MuonMinus and
G4MuonPlus).
Important notice: Don't forget to integrate the physics constructor class of the previous exercise into the full example application. The physics constructor should be registered in the general physics list when the user gives a proper messenger command.