using option '-treename HLTesdTree' for EsdCollector, adding default parameter for...
[u/mrichter/AliRoot.git] / PYTHIA8 / pythia8130 / include / BoseEinstein.h
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5ad4eb21 1// Bose-Einstein.h is a part of the PYTHIA event generator.
2// Copyright (C) 2008 Torbjorn Sjostrand.
3// PYTHIA is licenced under the GNU GPL version 2, see COPYING for details.
4// Please respect the MCnet Guidelines, see GUIDELINES for details.
5
6// This file contains the classes to handle Bose-Einstein effects.
7// BoseEinsteinHadron: simple working container for particle momenta.
8// BoseEinstein: main class to perform the task.
9
10#ifndef Pythia8_BoseEinstein_H
11#define Pythia8_BoseEinstein_H
12
13#include "Basics.h"
14#include "Event.h"
15#include "ParticleData.h"
16#include "PythiaStdlib.h"
17#include "Settings.h"
18
19namespace Pythia8 {
20
21//**************************************************************************
22
23// The BoseEinsteinHadron class is a simple container for studied hadrons.
24
25class BoseEinsteinHadron {
26
27public:
28
29 // Constructors.
30 BoseEinsteinHadron() : id(0), iPos(0), p(0.), pShift(0.), pComp(0.),
31 m2(0.) {}
32 BoseEinsteinHadron(int idIn, int iPosIn, Vec4 pIn, double mIn) :
33 id(idIn), iPos(iPosIn), p(pIn), pShift(0.), pComp(0.) {m2 = mIn*mIn;}
34
35 // Information on hadron - all public.
36 int id, iPos;
37 Vec4 p, pShift, pComp;
38 double m2;
39
40};
41
42//**************************************************************************
43
44// The BoseEinstein class shifts the momenta of identical particles relative
45// to each other, to simulate Bose-Einstein effects to some approximation.
46
47class BoseEinstein {
48
49public:
50
51 // Constructor.
52 BoseEinstein() {}
53
54 // Find settings. Precalculate table used to find momentum shifts.
55 bool init(Info* infoPtrIn);
56
57 // Perform Bose-Einstein corrections on an event.
58 bool shiftEvent( Event& event);
59
60private:
61
62 // Constants: could only be changed in the code itself.
63 static const int IDHADRON[9], ITABLE[9], NCOMPSTEP;
64 static const double STEPSIZE, Q2MIN, COMPRELERR, COMPFACMAX;
65
66 // Initialization data, read from Settings.
67 bool doPion, doKaon, doEta;
68 double lambda, QRef;
69
70 // Pointer to various information on the generation.
71 Info* infoPtr;
72
73 // Table of momentum shifts for different hadron species.
74 int nStep[4], nStep3[4], nStored[10];
75 double QRef2, QRef3, R2Ref, R2Ref2, R2Ref3, mHadron[9],
76 mPair[4], m2Pair[4], deltaQ[4], deltaQ3[4], maxQ[4], maxQ3[4];
77 double shift[4][200], shift3[4][200];
78
79 // Vector of hadrons to study.
80 vector<BoseEinsteinHadron> hadronBE;
81
82 // Calculate shift and (unnormalized) compensation for pair.
83 void shiftPair(int i1, int i2, int iHad);
84
85};
86
87//**************************************************************************
88
89} // end namespace Pythia8
90
91#endif // Pythia8_BoseEinstein_H
92