2019 Session 8 : Exercise

Code for download: session8_start.tar.gz

Exercise 8a:

  • Rotate Tube volume so that the tube symmetry axis is parallel with y-axis of the world reference frame.
    • Hint: See slide #14 in geometry presentation from Monday.
  • Complete the EDMagneticField class to define a magnetic field with B=1.0*tesla in the y-direction and which is limited to the Tube volume.
    • Hint: Set magnetic filed with use of the function void SetFieldManager(G4FieldManager *pFieldMgr, G4bool forceToAllDaughters);  defined for G4LogicalVolume class
  • After including a magnetic field, charged particles do not reach the second arm of the detector. Rotate the second arm by 30 degree and check that particles are again detected in the second arm.
    • Hint: You can use rotateY(G4double angle) function defined for G4ThreeVector to apply the rotation to the second arm position to place it where needed: 
      G4ThreeVector secondArmPosition(0, 0, zpos);
  • Add changes necessary for multi-threading and activate G4MTRunManager in main().
    Hint: Use G4AutoDelete to get magnetic field safely deleted in MT mode:
    // Register the field and its manager for deleting
  • When the magnetic field is implemented you can activate its visualization with the UI command:

Exercise 8b:

  • Re-implement calorimeter layers with use of G4PVReplica and add an additional level of 3 divisions in y axis.
    • Note: After adding the divisions in y axis (cells), the sensitive detector EDEmCalorimeterSD has to be associated with the new replica logical volume (cellLV). Also the code used to get the calorimeter layer number has to be adapted for this change in geometry.

Solution: session8_solution.tar.gz