include/Pythia8/BeamShape.h

0001 // BeamShape.h is a part of the PYTHIA event generator.
0002 // Copyright (C) 2024 Torbjorn Sjostrand.
0003 // PYTHIA is licenced under the GNU GPL v2 or later, see COPYING for details.
0004 // Please respect the MCnet Guidelines, see GUIDELINES for details.
0005
0006 // Header for classes to set beam momentum and interaction vertex spread.
0007
0008 #ifndef Pythia8_BeamShape_H
0009 #define Pythia8_BeamShape_H
0010
0011 #include "Pythia8/Basics.h"
0012 #include "Pythia8/PythiaStdlib.h"
0013 #include "Pythia8/Settings.h"
0014
0015 namespace Pythia8 {
0016
0017 //==========================================================================
0018
0019 // Base class to set beam momentum and interaction spot spread.
0020
0021 class BeamShape {
0022
0023 public:
0024
0025   // Constructor.
0026   BeamShape() : deltaPxA(), deltaPyA(), deltaPzA(), deltaPxB(), deltaPyB(),
0027     deltaPzB(), vertexX(), vertexY(), vertexZ(), vertexT(),
0028     allowMomentumSpread(), allowVertexSpread(), sigmaPxA(), sigmaPyA(),
0029     sigmaPzA(), maxDevA(), sigmaPxB(), sigmaPyB(), sigmaPzB(), maxDevB(),
0030     sigmaVertexX(), sigmaVertexY(), sigmaVertexZ(), maxDevVertex(),
0031     sigmaTime(), maxDevTime(), offsetX(), offsetY(), offsetZ(), offsetT(),
0032     rndmPtr() {}
0033
0034   // Destructor.
0035   virtual ~BeamShape() {}
0036
0037   // Initialize beam parameters.
0038   virtual void init( Settings& settings, Rndm* rndmPtrIn);
0039
0040   // Set the two beam momentum deviations and the beam vertex.
0041   virtual void pick();
0042
0043   // Methods to read out the choice made with the above method.
0044   Vec4 deltaPA() const {return Vec4( deltaPxA, deltaPyA, deltaPzA, 0);}
0045   Vec4 deltaPB() const {return Vec4( deltaPxB, deltaPyB, deltaPzB, 0);}
0046   Vec4 vertex()  const {return Vec4( vertexX, vertexY, vertexZ, vertexT);}
0047
0048 protected:
0049
0050   // Values to be set.
0051   double deltaPxA, deltaPyA, deltaPzA, deltaPxB, deltaPyB, deltaPzB,
0052          vertexX, vertexY, vertexZ, vertexT;
0053
0054   // Parameters of Gaussian parametrizations.
0055   bool   allowMomentumSpread, allowVertexSpread;
0056   double sigmaPxA, sigmaPyA, sigmaPzA, maxDevA, sigmaPxB, sigmaPyB,
0057          sigmaPzB, maxDevB, sigmaVertexX, sigmaVertexY, sigmaVertexZ,
0058          maxDevVertex, sigmaTime, maxDevTime, offsetX, offsetY,
0059          offsetZ, offsetT;
0060
0061   // Pointer to the random number generator.
0062   Rndm*  rndmPtr;
0063
0064 };
0065
0066 //==========================================================================
0067
0068 } // end namespace Pythia8
0069
0070 #endif // Pythia8_BeamShape_H