This example exercises the capability of tracking massive particles in a gravity field.

Credit goes to Erik Miller (Univ. of Northern British Columbia) and Garry Yan (Univ. of Toronto)

Classes Used

main()

GEOMETRY DEFINITION

As simple world G4Box with a G4UniformGravityField propagating momentum (G4EqGravityField) with G4ClassicalRK4(fEquation,8). The example uses the default gravity field on the earth's surface: gy = -9.81*m/s/s/c_light.

AN EVENT: THE PRIMARY GENERATOR

Uses an Ultra Cold Neutron (UCN) and G4ParticleGun with:
particleEnergy = G4UniformRand()*1e-7*eV

UCN are launched from (0,0,0) uniform into 4pi

PHYSICS

The simulation knows of only six particles: G4Neutron, G4Proton, G4Electron, G4AntiNeutrinoE, G4MuonPlus and G4MuonMinus

 RegisterPhysics(new G4StepLimiterPhysics());

G4StepLimiterPhysics defines G4StepLimiter and G4UserSpecialCuts

HOW TO START ?

This example handles the program arguments in a new way. It can be run with the following optional arguments:

% field06 [-m macro ] [-u UIsession] [-t nThreads] [-r randomSeed]

The -t option is available only in multi-threading mode and it allows the user to override the Geant4 default number of threads. The number of threads can be also set via G4FORCENUMBEROFTHREADS environment variable which has the top priority.

Execute field06 in 'batch' mode from macro files e.g.
```
% field06 -m field06.in > field06.out &
```

Execute field06 in 'interactive' mode with visualization e.g.

% field06
....
Idle> type your commands, for example:
Idle> run/beamOn 1
....