Gabriele Cosmo
76 lines
2.2 KiB
Plaintext
76 lines
2.2 KiB
Plaintext
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=========================================================
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Geant4 - an Object-Oriented Toolkit for Simulation in HEP
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=========================================================
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field06 Example
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---------------
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This example exercises the capability of tracking massive
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particles in a gravity field.
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Credit goes to Erik Miller (Univ. of Northern British Columbia) and
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Garry Yan (Univ. of Toronto)
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**************
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*Classes Used*
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**************
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1 - main()
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See field06.cc.
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2- GEOMETRY DEFINITION
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As simple world G4Box with a G4UniformGravityField propagating momentum
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(G4EqGravityField) with G4ClassicalRK4(fEquation,8). The example uses the
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default gravity field on the earth's surface: gy = -9.81*m/s/s/c_light.
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3- AN EVENT: THE PRIMARY GENERATOR
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Uses an Ultra Cold Neutron (UCN) and G4ParticleGun with:
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particleEnergy = G4UniformRand()*1e-7*eV
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UCN are launched from (0,0,0) uniform into 4pi
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4- PHYSICS
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The simulation knows of only four particles: G4Neutron, G4Proton,
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G4Electron and G4AntiNeutrinoE
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RegisterPhysics(new G4DecayPhysics());
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RegisterPhysics(new G4StepLimiterPhysics());
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G4VModularPhysicsList::ConstructProcess();
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G4StepLimiterPhysics defines G4StepLimiter and G4UserSpecialCuts
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5- User Action Classes
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F06EventAction:
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EndOfEventAction - draws trajectories in G4TrajectoryContainer
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6- HOW TO START ?
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This example handles the program arguments in a new way.
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It can be run with the following optional arguments:
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% OpNovice [-m macro ] [-u UIsession] [-t nThreads]
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The -t option is available only in multi-threading mode
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and it allows the user to override the Geant4 default number of
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threads. The number of threads can be also set via G4FORCENUMBEROFTHREADS
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environment variable which has the top priority.
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- execute field06 in 'batch' mode from macro files e.g.
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% field06 -m field06.in > field06.out &
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- execute field06 in 'interactive' mode with visualization e.g.
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% field60
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....
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Idle> type your commands, for example:
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Idle> run/beamOn 1
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....
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