Geant4 User's Guide for Application Developers - Geant4 - CERN

Detector Definition and ResponseTrack length scorersG4PSTrackLengthThe track length is defined as the sum of step lengths of the particles inside the cell. Bt default, the trackweight is not taken into account, but could be used as a multiplier of each step length if the Weighted() methodof this class object is invoked.G4PSPassageTrackLengthThe passage track length is the same as the track length in G4PSTrackLength, except that only tracks whichpass through the volume are taken into account. It means newly-generated or stopped tracks inside the cellare excluded from the calculation. By default, the track weight is not taken into account, but could be used asa multiplier of each step length if the Weighted() method of this class object is invoked.Deposited energy scorersG4PSEnergyDepositThis scorer stores a sum of particles' energy deposits at each step in the cell. The particle weight is multipliedat each step.G4PSDoseDepositIn some cases, dose is a more convenient way to evaluate the effect of energy deposit in a cell than simpledeposited energy. The dose deposit is defined by the sum of energy deposits at each step in a cell divided bythe mass of the cell. The mass is calculated from the density and volume of the cell taken from the methodsof G4VSolid and G4LogicalVolume. The particle weight is multiplied at each step.Current and flux scorersThere are two different definitions of a particle's flow for a given geometry. One is a current and the other is aflux. In our scorers, the current is simply defined as the number of particles (with the particle's weight) at a certainsurface or volume, while the flux takes the particle's injection angle to the geometry into account. The current andflux are usually defined at a surface, but volume current and volume flux are also provided.G4PSFlatSurfaceCurrentFlat surface current is a surface based scorer. The present implementation is limited to scoring only at the -Zsurface of a G4Box solid. The quantity is defined by the number of tracks that reach the surface. The user mustchoose a direction of the particle to be scored. The choices are fCurrent_In, fCurrent_Out, or fCurrent_InOut,one of which must be entered as the second argument of the constructor. Here, fCurrent_In scores incomingparticles to the cell, while fCurrent_Out scores only outgoing particles from the cell. fCurrent_InOut scoresboth directions. The current is multiplied by particle weight and is normalized for a unit area.G4PSSphereSurfaceCurrentSphere surface current is a surface based scorer, and similar to the G4PSFlatSurfaceCurrent. The only differenceis that the surface is defined at the inner surface of a G4Sphere solid.G4PSPassageCurrentPassage current is a volume-based scorer. The current is defined by the number of tracks that pass throughthe volume. A particle weight is applied at the exit point. A passage current is defined for a volume.G4PSFlatSurfaceFluxFlat surface flux is a surface based flux scorer. The surface flux is defined by the number of tracks that reach thesurface. The expression of surface flux is given by the sum of W/cos(t)/A, where W, t and A represent particleweight, injection angle of particle with respect to the surface normal, and area of the surface. The user mustenter one of the particle directions, fFlux_In, fFlux_Out, or fFlux_InOut in the constructor. Here, fFlux_Inscores incoming particles to the cell, while fFlux_Out scores outgoing particles from the cell. fFlux_InOutscores both directions.G4PSCellFluxCell flux is a volume based flux scorer. The cell flux is defined by a track length (L) of the particle insidea volume divided by the volume (V) of this cell. The track length is calculated by a sum of the step lengths133