[GaseousDetectorScorerers] time for each step is the mean of time at the...

[GaseousDetectorScorerers] time for each step is the mean of time at the begining and at the end of each step

NPSimulation/Scorers/GaseousDetectorScorers.cc

@@ -78,7 +78,7 @@ G4bool PS_GaseousDetector::ProcessHits(G4Step* aStep, G4TouchableHistory*) {
   int trackID  = aStep->GetTrack()->GetTrackID();
   double step_posZ = aStep->GetPostStepPoint()->GetPosition().z(); // z coordinate at the end of the step.
   t_Energy = aStep->GetTotalEnergyDeposit();  
-  t_Time   = aStep->GetPreStepPoint()->GetGlobalTime();  // DeltaT [ns] since the begining of the simulated event up to the begining of the step
+  t_Time   = 0.5*(aStep->GetPreStepPoint()->GetGlobalTime()+aStep->GetPostStepPoint()->GetGlobalTime());  // DeltaT [ns] since the begining of the simulated event up to the begining of the step
   t_ParticleName.push_back(particlename);
   t_TrackID.push_back(trackID);
   t_StepPosZ.push_back(step_posZ);