include/Geant4/G4ErrorFreeTrajState.hh

0001 //
0002 // ********************************************************************
0003 // * License and Disclaimer                                           *
0004 // *                                                                  *
0005 // * The  Geant4 software  is  copyright of the Copyright Holders  of *
0006 // * the Geant4 Collaboration.  It is provided  under  the terms  and *
0007 // * conditions of the Geant4 Software License,  included in the file *
0008 // * LICENSE and available at  http://cern.ch/geant4/license .  These *
0009 // * include a list of copyright holders.                             *
0010 // *                                                                  *
0011 // * Neither the authors of this software system, nor their employing *
0012 // * institutes,nor the agencies providing financial support for this *
0013 // * work  make  any representation or  warranty, express or implied, *
0014 // * regarding  this  software system or assume any liability for its *
0015 // * use.  Please see the license in the file  LICENSE  and URL above *
0016 // * for the full disclaimer and the limitation of liability.         *
0017 // *                                                                  *
0018 // * This  code  implementation is the result of  the  scientific and *
0019 // * technical work of the GEANT4 collaboration.                      *
0020 // * By using,  copying,  modifying or  distributing the software (or *
0021 // * any work based  on the software)  you  agree  to acknowledge its *
0022 // * use  in  resulting  scientific  publications,  and indicate your *
0023 // * acceptance of all terms of the Geant4 Software license.          *
0024 // ********************************************************************
0025 //
0026 //
0027 //
0028 // Class Description:
0029 //
0030 // Represents a free G4ErrorTrajState
0031 // It can be represented by the 5 variables
0032 //     1/p, lambda, phi, y_perp, z_perp
0033 // where lambda and phi are the dip and azimuthal angles related
0034 // to the momentum components in the following way:
0035 //            p_x = p cos(lambda) cos(phi)  ! lambda = 90 - theta
0036 //            p_y = p cos(lambda) sin(phi)
0037 //            p_z = p sin(lambda)
0038 // y_perp and z_perp are the coordinates of the trajectory in a
0039 // local orthonormal reference frame with the x_perp axis along the
0040 // particle direction, the y_perp being parallel to the x-y plane.
0041 //
0042 // This class also takes care of propagating the error associated to
0043 // the trajectory
0044
0045 // History:
0046 // - Created:   P. Arce
0047 // --------------------------------------------------------------------
0048
0049 #ifndef G4ErrorFreeTrajState_hh
0050 #define G4ErrorFreeTrajState_hh
0051
0052 #include "globals.hh"
0053
0054 #include "G4ErrorMatrix.hh"
0055
0056 #include "G4ErrorTrajState.hh"
0057 #include "G4ErrorFreeTrajParam.hh"
0058
0059 #include "G4Point3D.hh"
0060 #include "G4Vector3D.hh"
0061
0062 class G4ErrorSurfaceTrajState;
0063
0064 class G4ErrorFreeTrajState : public G4ErrorTrajState
0065 {
0066  public:  // with description
0067   G4ErrorFreeTrajState()
0068     : theFirstStep(true)
0069   {}
0070   G4ErrorFreeTrajState(const G4String& partName, const G4Point3D& pos,
0071                        const G4Vector3D& mom,
0072                        const G4ErrorTrajErr& errmat = G4ErrorTrajErr(5, 0));
0073   // Constructor by providing particle, position and momentum
0074
0075   G4ErrorFreeTrajState(const G4ErrorSurfaceTrajState& tpOS);
0076   // Constructor by providing G4ErrorSurfaceTrajState
0077
0078   ~G4ErrorFreeTrajState() {}
0079
0080   virtual G4int Update(const G4Track* aTrack);
0081   // update parameters from G4Track
0082
0083   virtual G4int PropagateError(const G4Track* aTrack);
0084   // propagate the error along the step
0085
0086   virtual void Dump(std::ostream& out = G4cout) const;
0087   // dump TrajState parameters
0088
0089   friend std::ostream& operator<<(std::ostream&,
0090                                   const G4ErrorFreeTrajState& ts);
0091
0092   // Set and Get methods
0093
0094   virtual void SetPosition(const G4Point3D pos)
0095   {
0096     SetParameters(pos, fMomentum);
0097   }
0098
0099   virtual void SetMomentum(const G4Vector3D& mom)
0100   {
0101     SetParameters(fPosition, mom);
0102   }
0103
0104   void SetParameters(const G4Point3D& pos, const G4Vector3D& mom)
0105   {
0106     fPosition = pos;
0107     fMomentum = mom;
0108     fTrajParam.SetParameters(pos, mom);
0109   }
0110
0111   G4ErrorFreeTrajParam GetParameters() const { return fTrajParam; }
0112
0113   G4ErrorMatrix GetTransfMat() const { return theTransfMat; }
0114
0115  private:
0116   void Init();
0117   // define TrajState type and build charge
0118
0119   G4int PropagateErrorMSC(const G4Track* aTrack);
0120   // add the error associated to multiple scattering
0121
0122   void CalculateEffectiveZandA(const G4Material* mate, double& effZ,
0123                                double& effA);
0124   // calculate effective Z and A (needed by PropagateErrorMSC)
0125
0126   G4int PropagateErrorIoni(const G4Track* aTrack);
0127   // add the error associated to ionization energy loss
0128
0129  private:
0130   G4ErrorFreeTrajParam fTrajParam;
0131
0132   G4ErrorMatrix theTransfMat;
0133
0134   G4bool theFirstStep;  // to count if transf mat is updated or initialized
0135 };
0136
0137 #endif