Geant4  10.03
G4PionZero.cc
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27 // $Id: G4PionZero.cc 79357 2014-02-25 10:06:54Z gcosmo $
28 //
29 //
30 // ----------------------------------------------------------------------
31 // GEANT 4 class implementation file
32 //
33 // History: first implementation, based on object model of
34 // 4th April 1996, G.Cosmo
35 // **********************************************************************
36 // New impelemenataion as an utility class M.Asai, 26 July 2004
37 // ----------------------------------------------------------------------
38 
39 #include "G4PionZero.hh"
40 #include "G4PhysicalConstants.hh"
41 #include "G4SystemOfUnits.hh"
42 #include "G4ParticleTable.hh"
43 
44 
46 #include "G4DalitzDecayChannel.hh"
47 #include "G4DecayTable.hh"
48 
49 // ######################################################################
50 // ### PIONZERO ###
51 // ######################################################################
52 
54 
56 {
57  if (theInstance !=0) return theInstance;
58  const G4String name = "pi0";
59  // search in particle table]
61  G4ParticleDefinition* anInstance = pTable->FindParticle(name);
62  if (anInstance ==0)
63  {
64  // create particle
65  //
66  // Arguments for constructor are as follows
67  // name mass width charge
68  // 2*spin parity C-conjugation
69  // 2*Isospin 2*Isospin3 G-parity
70  // type lepton number baryon number PDG encoding
71  // stable lifetime decay table
72  // shortlived subType anti_encoding
73 
74  anInstance = new G4ParticleDefinition(
75  name, 0.1349766*GeV, 7.73e-06*MeV, 0.0,
76  0, -1, +1,
77  2, 0, -1,
78  "meson", 0, 0, 111,
79  false, 8.52e-8*ns, NULL,
80  false, "pi", 111);
81 
82  // Life time is given from width
83  anInstance->SetPDGLifeTime( hbar_Planck/(anInstance->GetPDGWidth()) );
84 
85  //create Decay Table
86  G4DecayTable* table = new G4DecayTable();
87 
88  // create a decay channel
89  G4VDecayChannel* mode;
90  // pi0 -> gamma + gamma
91  mode = new G4PhaseSpaceDecayChannel("pi0",0.988,2,"gamma","gamma");
92  table->Insert(mode);
93  // pi0 -> gamma + e+ + e-
94  mode = new G4DalitzDecayChannel("pi0",0.012,"e-","e+");
95  table->Insert(mode);
96 
97  anInstance->SetDecayTable(table);
98  }
99  theInstance = reinterpret_cast<G4PionZero*>(anInstance);
100  return theInstance;
101 }
102 
104 {
105  return Definition();
106 }
107 
109 {
110  return Definition();
111 }
112 
void SetDecayTable(G4DecayTable *aDecayTable)
G4ParticleDefinition * FindParticle(G4int PDGEncoding)
void SetPDGLifeTime(G4double aLifeTime)
const char * name(G4int ptype)
static G4PionZero * PionZeroDefinition()
Definition: G4PionZero.cc:103
G4double GetPDGWidth() const
static G4PionZero * Definition()
Definition: G4PionZero.cc:55
static G4PionZero * PionZero()
Definition: G4PionZero.cc:108
void Insert(G4VDecayChannel *aChannel)
Definition: G4DecayTable.cc:60
static G4PionZero * theInstance
Definition: G4PionZero.hh:53
static G4ParticleTable * GetParticleTable()
static constexpr double GeV
Definition: G4SIunits.hh:217
static constexpr double MeV
Definition: G4SIunits.hh:214
#define ns
Definition: xmlparse.cc:614