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3.4 Run control and output

The execution control is performed in the GMAD input file through option and beam commands. How the results are recorded is controlledby the sample command. When the visualization is turned on, it is however controlled through command prompt and has different syntax (Geant4 syntax).

3.4.1 option

option, <name>=value,...;

the available options are options are

     
     nperfile
     beampipeRadius
     boxSize
     tunnelRadius
     beampipeThickness
     deltaChord
     deltaIntersection
     chordStepMinimum
     lengthSafety
     turnInteractions
     thresholdCutCharged
     thresholdCutPhotons
     useEMHadronic
     storeTrajectory
     stopTracks
     

For a more detailed description of how the option influence the tracking see Physics

Example :

3.4.2 beam

beam, particle=electron,energy=100, momentum=1,1,1;

3.4.3 sample

To record the tracking results one uses the sample command:

sample, range=<range>,particle=<particle>,values={value1,value2,...}

the parameters are

Example :

     sample, element=qd,particle=electron, values={x,px,y,py,e,id }; 
     sample, range=qd/qf:0.1*m,particle=photon, values={x,px,y,py,e,id }; 

3.4.4 use

use command selects the beam line for study

use, period=,range=

3.4.5 visualization control

when bdsim is invoked in interactive mode, the run is controlled by the Geant4 shell. Some examples

/run/beamOn 100 runs the simulation with 100 particles

To display help menu

/help;

For more details see Geant.