In Geant4.8.1 if the user set the weight of a generated particle in the PrimaraGeneratorAction, this weight is not correctly passed to the first track of an event. To illustrate this I did modify the novice example 03 by adding: a) at the end of void ExN03PrimaryGeneratorAction::GeneratePrimaries(G4Event* anEvent) the following two lines: anEvent->GetPrimaryVertex()->SetWeight(1000.); G4cout<<"Primary Weight "<<anEvent->GetPrimaryVertex()->SetWeight(1000.); b)at the end of void ExN03SteppingAction::UserSteppingAction(const G4Step* aStep) G4cout<<"Track Weight "<< aStep->GetTrack()->GetWeight()<<std::endl; When tracking a geantino in the geometry I get the print out reproduced at the end of this message. It is clear that the primary weight is not correctly passed to the first track. I think that the problem comes form the G4PrimaryTransformer.hh class. Indeed in one of my code where I use my own EventManager, by copying the G4PrimaryTransformer in a new class called MYPrimaryTransformer wihout changing anything in the class, and by using thius new class instead of G4PrimaryTransformer in my EventManager the problem is removed. Best Regards Laurent Desorgher ### Run 0 start. Start Run processing. Primary Weight 1000 ---> Begin of event: 0 --------- Ranecu engine status --------- Initial seed (index) = 0 Current couple of seeds = 9876, 54321 ---------------------------------------- ******************************************************************************** ************************* * G4Track Information: Particle = geantino, Track ID = 1, Parent ID = 0 ******************************************************************************** ************************* Step# X Y Z KineE dEStep StepLeng TrakLeng Volume Process 0 -9 cm 0 fm 0 fm 300 MeV 0 eV 0 fm 0 fm World initStep 1 -7.5 cm 0 fm 0 fm 300 MeV 0 eV 1.5 cm 1.5 cm World Transportation Track Weight 1 2 -6.5 cm 0 fm 0 fm 300 MeV 0 eV 1 cm 2.5 cm Lead Transportation Track Weight 1 3 -6 cm 0 fm 0 fm 300 MeV 0 eV 5 mm 3 cm li quidArgon Transportation Track Weight 1 4 -5 cm 0 fm 0 fm 300 MeV 0 eV 1 cm 4 cm Lead Transportation Track Weight 1 5 -4.5 cm 0 fm 0 fm 300 MeV 0 eV 5 mm 4.5 cm li quidArgon Transportation Track Weight 1 6 -3.5 cm 0 fm 0 fm 300 MeV 0 eV 1 cm 5.5 cm Lead Transportation Track Weight 1 7 -3 cm 0 fm 0 fm 300 MeV 0 eV 5 mm 6 cm li quidArgon Transportation Track Weight 1 8 -2 cm 0 fm 0 fm 300 MeV 0 eV 1 cm 7 cm Lead Transportation Track Weight 1 9 -1.5 cm 0 fm 0 fm 300 MeV 0 eV 5 mm 7.5 cm li quidArgon Transportation Track Weight 1 10 -5 mm 0 fm 0 fm 300 MeV 0 eV 1 cm 8.5 cm Lead Transportation Track Weight 1 11 0 fm 0 fm 0 fm 300 MeV 0 eV 5 mm 9 cm li quidArgon Transportation Track Weight 1 12 1 cm 0 fm 0 fm 300 MeV 0 eV 1 cm 10 cm Lead Transportation Track Weight 1 13 1.5 cm 0 fm 0 fm 300 MeV 0 eV 5 mm 10.5 cm li quidArgon Transportation Track Weight 1 14 2.5 cm 0 fm 0 fm 300 MeV 0 eV 1 cm 11.5 cm Lead Transportation Track Weight 1 15 3 cm 0 fm 0 fm 300 MeV 0 eV 5 mm 12 cm li quidArgon Transportation Track Weight 1 16 4 cm 0 fm 0 fm 300 MeV 0 eV 1 cm 13 cm Lead Transportation Track Weight 1 17 4.5 cm 0 fm 0 fm 300 MeV 0 eV 5 mm 13.5 cm li quidArgon Transportation Track Weight 1 18 5.5 cm 0 fm 0 fm 300 MeV 0 eV 1 cm 14.5 cm Lead Transportation Track Weight 1 19 6 cm 0 fm 0 fm 300 MeV 0 eV 5 mm 15 cm li quidArgon Transportation Track Weight 1 20 7 cm 0 fm 0 fm 300 MeV 0 eV 1 cm 16 cm Lead Transportation Track Weight 1 21 7.5 cm 0 fm 0 fm 300 MeV 0 eV 5 mm 16.5 cm li quidArgon Transportation Track Weight 1 22 9 cm 0 fm 0 fm 300 MeV 0 eV 1.5 cm 18 cm Ou tOfWorld Transportation Track Weight 1.0000002 ---> End of event: 0 Absorber: total energy: 0 eV total track length: 0 fm Gap: total energy: 0 eV total track length: 0 fm Run terminated. Run Summary Number of events processed : 1 User=0s Real=0s Sys=0s
The weight for an event is supposed to be multiplier for the weights of tracks. It means, in your stepping action, you have to multiply the event weight to the track weight. It is just a matter of design and it is our design decision.
Dear Makoto, Contrary to what you seem to say in your last comment, the first track of an event received in Geant4 the weight of the primary vertex. Anyway,the problem that I did encounter was due to my Geant4 installation. When installing Geant4.8.1 I did copy all the include files in one directory. Altough by running Configure.sh for the installation of the patches 1 and 2 I did choose to copy the include files in one directory, it seems that the new include files were not correctly copied. By removing the include directory ( and therefore by using the include files directly from the source tree) the problem is solved. In conclusion I do agree also that the problem is resolved. Thank you for your help Best regards Laurent
> When installing Geant4.8.1 I did copy all the include files in one directory. > Altough by running Configure.sh for the installation of the patches 1 and 2 > I did choose to copy the include files in one directory, it seems that the > new include files were not correctly copied. If you choose to install all headers in a single directory through Configure, you should remember to execute all the installation steps: $ ./Configure -build $ ./Configure -install <-- here the headers get installed !! $ ./Configure <-- to generate the configuration scripts to source afterwards
