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Reference Guide
TParticle.h
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1// @(#)root/eg:$Id$
2// Author: Rene Brun , Federico Carminati 26/04/99
3
4/*************************************************************************
5 * Copyright (C) 1995-2000, Rene Brun and Fons Rademakers. *
6 * All rights reserved. *
7 * *
8 * For the licensing terms see $ROOTSYS/LICENSE. *
9 * For the list of contributors see $ROOTSYS/README/CREDITS. *
10 *************************************************************************/
11//////////////////////////////////////////////////////////////////////////
12// //
13// TParticle: defines equivalent of HEPEVT particle //
14//////////////////////////////////////////////////////////////////////////
15
16#ifndef ROOT_TParticle
17#define ROOT_TParticle
18
19#include "TNamed.h"
20#include "TAttLine.h"
21#include "TAtt3D.h"
22#include "TLorentzVector.h"
23
24class TParticlePDG;
25
26class TParticle : public TObject, public TAttLine, public TAtt3D {
27
28
29protected:
30
31 Int_t fPdgCode; // PDG code of the particle
32 Int_t fStatusCode; // generation status code
33 Int_t fMother[2]; // Indices of the mother particles
34 Int_t fDaughter[2]; // Indices of the daughter particles
35 Float_t fWeight; // particle weight
36
37 Double_t fCalcMass; // Calculated mass
38
39 Double_t fPx; // x component of momentum
40 Double_t fPy; // y component of momentum
41 Double_t fPz; // z component of momentum
42 Double_t fE; // Energy
43
44 Double_t fVx; // x of production vertex
45 Double_t fVy; // y of production vertex
46 Double_t fVz; // z of production vertex
47 Double_t fVt; // t of production vertex
48
49 Double_t fPolarTheta; // Polar angle of polarisation
50 Double_t fPolarPhi; // azymutal angle of polarisation
51
52 mutable TParticlePDG* fParticlePDG; //! reference to the particle record in PDG database
53 //----------------------------------------------------------------------------
54 // functions
55 //----------------------------------------------------------------------------
56public:
57 // ****** constructors and destructor
58 TParticle();
59
60 TParticle(Int_t pdg, Int_t status,
61 Int_t mother1, Int_t mother2,
62 Int_t daughter1, Int_t daughter2,
63 Double_t px, Double_t py, Double_t pz, Double_t etot,
64 Double_t vx, Double_t vy, Double_t vz, Double_t time);
65
66 TParticle(Int_t pdg, Int_t status,
67 Int_t mother1, Int_t mother2,
68 Int_t daughter1, Int_t daughter2,
69 const TLorentzVector &p,
70 const TLorentzVector &v);
71
72 TParticle(const TParticle &part);
73
74 virtual ~TParticle();
75
77
78// virtual TString* Name () const { return fName.Data(); }
79// virtual char* GetName() const { return fName.Data(); }
80
81 Double_t Ek () const { return fE-fCalcMass; }
82 Int_t GetStatusCode () const { return fStatusCode; }
83 Int_t GetPdgCode () const { return fPdgCode; }
84 Int_t GetFirstMother () const { return fMother[0]; }
85 Int_t GetMother (Int_t i) const { return fMother[i]; }
86 Int_t GetSecondMother () const { return fMother[1]; }
87 Bool_t IsPrimary () const { return fMother[0]>-1 ? kFALSE : kTRUE; } //Is this particle primary one?
88 Int_t GetFirstDaughter() const { return fDaughter[0]; }
89 Int_t GetDaughter (Int_t i) const { return fDaughter[i]; }
90 Int_t GetLastDaughter () const { return fDaughter[1]; }
91 Double_t GetCalcMass () const { return fCalcMass; }
92 Double_t GetMass () const;
93 Int_t GetNDaughters () const { return fDaughter[1]>0 ? fDaughter[1]-fDaughter[0]+1 : 0;}
94 Float_t GetWeight () const { return fWeight; }
95 void GetPolarisation(TVector3 &v) const;
96 TParticlePDG* GetPDG (Int_t mode = 0) const;
97 Int_t Beauty () const;
98 Int_t Charm () const;
99 Int_t Strangeness () const;
100 Double_t PhiX () const { return TMath::Pi()+TMath::ATan2(-fPz,-fPy); } // note that PhiX() returns an angle between 0 and 2pi
101 Double_t PhiY () const { return TMath::Pi()+TMath::ATan2(-fPx,-fPz); } // note that PhiY() returns an angle between 0 and 2pi
102 Double_t PhiZ () const { return TMath::Pi()+TMath::ATan2(-fPy,-fPx); } // note that PhiZ() returns an angle between 0 and 2pi
103 Double_t ThetaX () const { return (fPx==0)?TMath::PiOver2():TMath::ACos(fPx/P()); }
104 Double_t ThetaY () const { return (fPy==0)?TMath::PiOver2():TMath::ACos(fPy/P()); }
105 Double_t ThetaZ () const { return (fPz==0)?TMath::PiOver2():TMath::ACos(fPz/P()); }
106 Double_t GetPolarTheta () const { return fPolarTheta; }
107 Double_t GetPolarPhi () const { return fPolarPhi; }
108 void GetPolarisation (Double_t &theta, Double_t &phi) const { theta = fPolarTheta; phi = fPolarPhi; }
109 void SetPolarTheta (Double_t theta) { fPolarTheta = theta; }
110 void SetPolarPhi (Double_t phi) { fPolarPhi = phi; }
111 void SetPolarisation (Double_t theta, Double_t phi) { fPolarTheta = theta; fPolarPhi = phi; }
112 void Momentum(TLorentzVector &v) const { v.SetPxPyPzE(fPx,fPy,fPz,fE); }
113 void ProductionVertex(TLorentzVector &v) const { v.SetXYZT(fVx,fVy,fVz,fVt); }
114
115 Double_t Theta(const TParticle &p) // Returns the angle between momenta of particles
116 {
117 Double_t v = P()*p.P();
118 if (v == 0) v = 1; else v = (fPx*p.Px()+fPy*p.Py()+fPz*p.Pz())/v;
119 if (v > 1) v = 1; else if (v < -1) v = -1; // just a precaution
120 return TMath::ACos(v);
121 }
122
123// ****** redefine several most oftenly used methods of LORENTZ_VECTOR
124
125 Double_t Vx () const { return fVx; }
126 Double_t Vy () const { return fVy; }
127 Double_t Vz () const { return fVz; }
128 Double_t T () const { return fVt; }
129 Double_t R () const { return TMath::Sqrt(fVx*fVx+fVy*fVy); } //Radius of production vertex in cylindrical system
130 Double_t Rho () const { return TMath::Sqrt(fVx*fVx+fVy*fVy+fVz*fVz); } //Radius of production vertex in spherical system
131 Double_t Px () const { return fPx; }
132 Double_t Py () const { return fPy; }
133 Double_t Pz () const { return fPz; }
134 Double_t P () const { return TMath::Sqrt(fPx*fPx+fPy*fPy+fPz*fPz); }
135 Double_t Pt () const { return TMath::Sqrt(fPx*fPx+fPy*fPy); }
136 Double_t Energy () const { return fE; }
137 Double_t Eta () const
138 {
139 Double_t pmom = P();
140 if (pmom != TMath::Abs(fPz)) return 0.5*TMath::Log((pmom+fPz)/(pmom-fPz));
141 else return 1.e30;
142 }
143 Double_t Y () const
144 {
145 if (fE != TMath::Abs(fPz)) return 0.5*TMath::Log((fE+fPz)/(fE-fPz));
146 else return 1.e30;
147 }
148
149 Double_t Phi () const { return TMath::Pi()+TMath::ATan2(-fPy,-fPx); } // note that Phi() returns an angle between 0 and 2pi
150 Double_t Theta () const { return (fPz==0)?TMath::PiOver2():TMath::ACos(fPz/P()); }
151
152 // setters
153
154 void SetFirstMother (int code) { fMother[0] = code ; }
155 void SetMother (int i, int code) { fMother[i] = code ; }
156 void SetLastMother (int code) { fMother[1] = code ; }
157 void SetFirstDaughter(int code) { fDaughter[0] = code ; }
158 void SetDaughter(int i, int code) { fDaughter[i] = code ; }
159 void SetLastDaughter(int code) { fDaughter[1] = code ; }
160 void SetCalcMass(Double_t mass) { fCalcMass=mass;}
161 void SetPdgCode(Int_t pdg);
162 void SetPolarisation(Double_t polx, Double_t poly, Double_t polz);
163 void SetPolarisation(const TVector3& v) {SetPolarisation(v.X(), v.Y(), v.Z());}
164 void SetStatusCode(int status) {fStatusCode = status;}
165 void SetWeight(Float_t weight = 1) {fWeight = weight; }
166 void SetMomentum(Double_t px, Double_t py, Double_t pz, Double_t e) {fPx=px; fPy=py; fPz=pz; fE=e;}
167 void SetMomentum(const TLorentzVector& p) {SetMomentum(p.Px(),p.Py(),p.Pz(),p.Energy());}
168 void SetProductionVertex(Double_t vx, Double_t vy, Double_t vz, Double_t t) {fVx=vx; fVy=vy; fVz=vz; fVt=t;}
169 void SetProductionVertex(const TLorentzVector& v) {SetProductionVertex(v.X(),v.Y(),v.Z(),v.T());}
170
171 // ****** overloaded functions of TObject
172
173 virtual void Paint(Option_t *option = "");
174 virtual void Print(Option_t *option = "") const;
175 virtual void Sizeof3D() const;
176 virtual Int_t DistancetoPrimitive(Int_t px, Int_t py);
177 virtual void ExecuteEvent(Int_t event, Int_t px, Int_t py);
178 virtual const char *GetName() const;
179 virtual const char *GetTitle() const;
180
181
182 ClassDef(TParticle,2) // TParticle vertex particle information
183};
184
185#endif
#define e(i)
Definition: RSha256.hxx:103
int Int_t
Definition: RtypesCore.h:43
const Bool_t kFALSE
Definition: RtypesCore.h:90
bool Bool_t
Definition: RtypesCore.h:61
double Double_t
Definition: RtypesCore.h:57
float Float_t
Definition: RtypesCore.h:55
const Bool_t kTRUE
Definition: RtypesCore.h:89
const char Option_t
Definition: RtypesCore.h:64
#define ClassDef(name, id)
Definition: Rtypes.h:322
Use this attribute class when an object should have 3D capabilities.
Definition: TAtt3D.h:19
Line Attributes class.
Definition: TAttLine.h:18
Double_t Energy() const
Double_t Px() const
Double_t Pz() const
Double_t Py() const
Mother of all ROOT objects.
Definition: TObject.h:37
Description of the static properties of a particle.
Definition: TParticlePDG.h:19
Description of the dynamic properties of a particle.
Definition: TParticle.h:26
virtual Int_t DistancetoPrimitive(Int_t px, Int_t py)
Compute distance from point px,py to a primary track.
Definition: TParticle.cxx:215
Int_t fDaughter[2]
Definition: TParticle.h:34
Double_t GetMass() const
Return nominal particle mass from PDG table.
Definition: TParticle.cxx:178
Double_t fVy
Definition: TParticle.h:45
Double_t fPx
Definition: TParticle.h:39
Double_t Px() const
Definition: TParticle.h:131
TParticlePDG * fParticlePDG
Definition: TParticle.h:52
Double_t Ek() const
Definition: TParticle.h:81
Double_t Py() const
Definition: TParticle.h:132
Int_t GetNDaughters() const
Definition: TParticle.h:93
Int_t GetStatusCode() const
Definition: TParticle.h:82
Double_t fPolarTheta
Definition: TParticle.h:49
void GetPolarisation(TVector3 &v) const
Return particle polarisation.
Definition: TParticle.cxx:284
void SetMother(int i, int code)
Definition: TParticle.h:155
TParticle & operator=(const TParticle &)
Equal operator.
Definition: TParticle.cxx:134
Double_t Energy() const
Definition: TParticle.h:136
Double_t PhiY() const
Definition: TParticle.h:101
void ProductionVertex(TLorentzVector &v) const
Definition: TParticle.h:113
void SetPolarPhi(Double_t phi)
Definition: TParticle.h:110
Double_t Y() const
Definition: TParticle.h:143
Double_t R() const
Definition: TParticle.h:129
virtual void ExecuteEvent(Int_t event, Int_t px, Int_t py)
Execute action corresponding to one event.
Definition: TParticle.cxx:249
void SetMomentum(Double_t px, Double_t py, Double_t pz, Double_t e)
Definition: TParticle.h:166
Int_t GetPdgCode() const
Definition: TParticle.h:83
void SetPolarisation(Double_t theta, Double_t phi)
Definition: TParticle.h:111
Float_t GetWeight() const
Definition: TParticle.h:94
void SetDaughter(int i, int code)
Definition: TParticle.h:158
Double_t GetCalcMass() const
Definition: TParticle.h:91
Float_t fWeight
Definition: TParticle.h:35
Int_t GetFirstDaughter() const
Definition: TParticle.h:88
void SetLastDaughter(int code)
Definition: TParticle.h:159
Int_t Beauty() const
Return beauty quantum number.
Definition: TParticle.cxx:186
TParticlePDG * GetPDG(Int_t mode=0) const
Returns a pointer to the TParticlePDG object using the pdgcode.
Definition: TParticle.cxx:273
Double_t P() const
Definition: TParticle.h:134
Double_t fVz
Definition: TParticle.h:46
void SetProductionVertex(const TLorentzVector &v)
Definition: TParticle.h:169
Double_t ThetaZ() const
Definition: TParticle.h:105
Double_t ThetaY() const
Definition: TParticle.h:104
Double_t ThetaX() const
Definition: TParticle.h:103
Int_t Charm() const
Return charm quantum number.
Definition: TParticle.cxx:194
virtual ~TParticle()
destructor
Definition: TParticle.cxx:171
virtual void Print(Option_t *option="") const
Print the internals of the primary vertex particle.
Definition: TParticle.cxx:340
Double_t fCalcMass
Definition: TParticle.h:37
Double_t Pz() const
Definition: TParticle.h:133
Double_t Theta() const
Definition: TParticle.h:150
Int_t GetFirstMother() const
Definition: TParticle.h:84
Double_t Vy() const
Definition: TParticle.h:126
Int_t fPdgCode
Definition: TParticle.h:31
Double_t fE
Definition: TParticle.h:42
Double_t fVt
Definition: TParticle.h:47
Double_t T() const
Definition: TParticle.h:128
virtual void Sizeof3D() const
Return total X3D size of this primary.
Definition: TParticle.cxx:389
void SetCalcMass(Double_t mass)
Definition: TParticle.h:160
Double_t fPz
Definition: TParticle.h:41
TParticle()
reference to the particle record in PDG database
Definition: TParticle.cxx:63
Bool_t IsPrimary() const
Definition: TParticle.h:87
virtual const char * GetName() const
Return particle name.
Definition: TParticle.cxx:257
void SetFirstDaughter(int code)
Definition: TParticle.h:157
void SetStatusCode(int status)
Definition: TParticle.h:164
Double_t Pt() const
Definition: TParticle.h:135
void SetPdgCode(Int_t pdg)
Change the PDG code for this particle.
Definition: TParticle.cxx:353
Double_t Vx() const
Definition: TParticle.h:125
Double_t PhiX() const
Definition: TParticle.h:100
Double_t Phi() const
Definition: TParticle.h:149
void SetMomentum(const TLorentzVector &p)
Definition: TParticle.h:167
Double_t fVx
Definition: TParticle.h:44
Double_t fPy
Definition: TParticle.h:40
Double_t Eta() const
Definition: TParticle.h:137
Int_t GetDaughter(Int_t i) const
Definition: TParticle.h:89
Int_t fStatusCode
Definition: TParticle.h:32
Double_t GetPolarTheta() const
Definition: TParticle.h:106
Double_t Rho() const
Definition: TParticle.h:130
void SetWeight(Float_t weight=1)
Definition: TParticle.h:165
virtual void Paint(Option_t *option="")
Paint a primary track.
Definition: TParticle.cxx:311
void SetPolarTheta(Double_t theta)
Definition: TParticle.h:109
void SetLastMother(int code)
Definition: TParticle.h:156
void GetPolarisation(Double_t &theta, Double_t &phi) const
Definition: TParticle.h:108
Double_t Theta(const TParticle &p)
Definition: TParticle.h:115
Double_t fPolarPhi
Definition: TParticle.h:50
void SetPolarisation(const TVector3 &v)
Definition: TParticle.h:163
void SetFirstMother(int code)
Definition: TParticle.h:154
Int_t GetMother(Int_t i) const
Definition: TParticle.h:85
void SetProductionVertex(Double_t vx, Double_t vy, Double_t vz, Double_t t)
Definition: TParticle.h:168
Int_t Strangeness() const
Return strangeness quantum number.
Definition: TParticle.cxx:202
Double_t GetPolarPhi() const
Definition: TParticle.h:107
Double_t PhiZ() const
Definition: TParticle.h:102
Int_t fMother[2]
Definition: TParticle.h:33
void Momentum(TLorentzVector &v) const
Definition: TParticle.h:112
Double_t Vz() const
Definition: TParticle.h:127
Int_t GetLastDaughter() const
Definition: TParticle.h:90
virtual const char * GetTitle() const
Return particle title.
Definition: TParticle.cxx:298
Int_t GetSecondMother() const
Definition: TParticle.h:86
TVector3 is a general three vector class, which can be used for the description of different vectors ...
Definition: TVector3.h:22
Double_t ACos(Double_t)
Definition: TMath.h:658
constexpr Double_t PiOver2()
Definition: TMath.h:52
Double_t ATan2(Double_t y, Double_t x)
Definition: TMath.h:669
Double_t Log(Double_t x)
Definition: TMath.h:750
Double_t Sqrt(Double_t x)
Definition: TMath.h:681
constexpr Double_t Pi()
Definition: TMath.h:38
Short_t Abs(Short_t d)
Definition: TMathBase.h:120