All of AlongSepDoit’s are always invoked if provided.

AlongStepDoIt’s are invoked in the phase G4SteppingManger is transporting a particle by one step. Each change to the track information is recorded and accumulated in G4Step. However, track information themselves (data members G4Track) are not modified.

After all AlongStepDoIt's are invoked, G4Track data members will be updated by referring to G4Step.

AtRestDoIt’s can only happen to stopped particles and only if the corresponding GPIL method returns the minimum value among the processes, or the corresponding force flag is set.

AtRestDoIt’s are invoked at the time when G4SteppingManager is just before to start one step. At this time, only meaningful information in G4Step are ones related to the beginning of the step and the previous step.

Each process can have one, two or three “DoIt” methods to interface with the Stepping Manager

• AtRestDoIt, AlongStepDoIt, PostStepDoIt

Each process can propose or force to invoke itself via GetPhysicalInteractionLength (GPIL)

• AtRestPhysicalInteractionLength and etc.

Generalization of “processes”

• physics, transportation and also parameterization
• unified treatment from the view of stepping manager
• make ease the implementation of new physics process
  • no knowledge on tracking/stepping are necessary
  • people who implement new process only touch process category

We have introduced the new design for tracking/process interface after the last workshop at Vancouver. The change has done in early this year.

Detailed documents on new tracking/stepping design are available:

• geant4alpha/documents/tracking/NewDesignDoc.txt

Mandate

• Prepare “Item list” for every category
• Successively shift to the Examples Working Group

Member

John Allison, Makoto Asai (Chair), Andrea Dell’Acqua,

Hisaya Kurashige, Michel Maire, Marc Verderi

There are two levels of items, “novice” and “advanced”.

“Item list” will be posted on Web and be announced to all of colleagues very soon.