Introduction to GEANT4
From UCL HEP PBT Wiki
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=== <span style="color:#000080"> Track </span> === | === <span style="color:#000080"> Track </span> === | ||
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| + | Track is a snapshot of a particle and it is represented by <span style="color:#ff0000"> G4Track </span> class. At the end of the event the track objects do not exist. Tracks are updated by steps. At the end of each step the state of a track can be changed (killed, suspended, postponed). | ||
=== <span style="color:#000080"> Step </span> === | === <span style="color:#000080"> Step </span> === | ||
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| + | Step has two points and information about the particle e.g. energy loss on the step. A step is represented by <span style="color:#ff0000"> G4Step </span> and <span style="color:#ff0000"> G4StepPoint </span> classes. G4UserSteppingAction is optional class where you can kill, suspend, postpone a track. | ||
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| + | Status is attached to each <span style="color:#ff0000"> G4StepPoint </span> to show how step was determined. You can use PostStepPoint to get status of current step and PreStepPoint to get status of previous step. For example to get the x coordinate of a step you do the following: | ||
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| + | <pre style="color: #800000; background-color: #dcdcdc"> | ||
| + | G4StepPoint* prePoint = step->GetPreStepPoint(); | ||
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| + | G4double x1 = prePoint->GetPosition().x(); | ||
| + | </pre> | ||
=== <span style="color:#000080"> Trajectory </span> === | === <span style="color:#000080"> Trajectory </span> === | ||
| - | + | Trajectories are represented by classes <span style="color:#ff0000"> G4Trajectory </span> and <span style="color:#ff0000"> G4TrajectoryPoint </span>. <span style="color:#ff0000"> G4Trajectory </span> class copies some of the <span style="color:#ff0000"> G4Track </span> class information. <span style="color:#ff0000"> G4TrajectoryPoint </span> is the class which copies some of <span style="color:#ff0000"> G4Step </span> information. | |
