Geant4  10.02
G4EvaporationChannel.cc
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26 // $Id: G4EvaporationChannel.cc 90273 2015-05-22 10:20:32Z gcosmo $
27 //
28 //J.M. Quesada (August2008). Based on:
29 //
30 // Hadronic Process: Nuclear De-excitations
31 // by V. Lara (Oct 1998)
32 //
33 // Modified:
34 // 03-09-2008 J.M. Quesada for external choice of inverse cross section option
35 // 06-09-2008 J.M. Quesada Also external choices have been added for superimposed
36 // Coulomb barrier (if useSICB is set true, by default is false)
37 // 17-11-2010 V.Ivanchenko in constructor replace G4VEmissionProbability by
38 // G4EvaporationProbability and do not new and delete probability
39 // object at each call; use G4Pow
40 
41 #include "G4EvaporationChannel.hh"
42 #include "G4PairingCorrection.hh"
43 #include "G4NucleiProperties.hh"
44 #include "G4Pow.hh"
45 #include "G4Log.hh"
46 #include "G4Exp.hh"
48 #include "G4PhysicalConstants.hh"
49 #include "G4SystemOfUnits.hh"
50 #include "Randomize.hh"
51 #include "G4Alpha.hh"
52 
54  const G4String & aName,
56  G4VCoulombBarrier* barrier):
57  G4VEvaporationChannel(aName),
58  theA(anA),
59  theZ(aZ),
60  theProbability(aprob),
61  theCoulombBarrier(barrier),
62  EmissionProbability(0.0),
63  MaximalKineticEnergy(-1000.0)
64 {
65  ResidualA = 0;
66  ResidualZ = 0;
71 }
72 
74 {
75  delete theLevelDensityPtr;
76 }
77 
79 {
80  //for inverse cross section choice
82  // for superimposed Coulomb Barrier for inverse cross sections
84 
86 }
87 
89 {
90  G4int FragA = fragment->GetA_asInt();
91  G4int FragZ = fragment->GetZ_asInt();
92  ResidualA = FragA - theA;
93  ResidualZ = FragZ - theZ;
94  //G4cout << "G4EvaporationChannel::Initialize Z= " << theZ << " A= " << theA
95  // << " FragZ= " << FragZ << " FragA= " << FragA << G4endl;
96  EmissionProbability = 0.0;
97 
98  // Only channels which are physically allowed are taken into account
99  if (ResidualA >= ResidualZ && ResidualZ > 0 && ResidualA >= theA) {
100 
101  //Effective excitation energy
102  G4double ExEnergy = fragment->GetExcitationEnergy();
103  G4double delta0 =
105  G4double delta1 =
108  G4double FragmentMass = fragment->GetGroundStateMass();
109  G4double Etot = FragmentMass + ExEnergy;
110  G4double ResMass = ResidualMass + delta1;
111 
112  if(ExEnergy >= delta0 && Etot > ResMass + EvaporatedMass) {
113 
114  // Maximal Kinetic Energy
115  MaximalKineticEnergy = ((Etot-ResMass)*(Etot+ResMass)
117 
118  // The threshold for charged particle emission must be set to
119  // 0 if Coulomb cutoff is included in the cross sections
120  // Of course for OPTxs=0 we have the Coulomb barrier
121 
122  CoulombBarrier = 0.0;
123  if (OPTxs==0 || useSICB) {
124  CoulombBarrier =
126  }
129  TotalProbability(*fragment, CoulombBarrier, MaximalKineticEnergy);
130  }
131  }
132  }
133  //G4cout << "G4EvaporationChannel:: probability= "
134  // << EmissionProbability << G4endl;
135  return EmissionProbability;
136 }
137 
139 {
140  G4Fragment* evFragment = 0;
141  G4double evEnergy = EvaporatedMass +
144 
146  (std::sqrt((evEnergy - EvaporatedMass)*(evEnergy + EvaporatedMass))));
147 
148  G4LorentzVector EvaporatedMomentum(momentum, evEnergy);
149  G4LorentzVector ResidualMomentum = theNucleus->GetMomentum();
150  EvaporatedMomentum.boost(ResidualMomentum.boostVector());
151 
152  evFragment = new G4Fragment(theA,theZ,EvaporatedMomentum);
153  ResidualMomentum -= EvaporatedMomentum;
154  theNucleus->SetZandA_asInt(ResidualZ, ResidualA);
155  theNucleus->SetMomentum(ResidualMomentum);
156 
157  return evFragment;
158 }
159 
161 {
162  G4FragmentVector * theResult = new G4FragmentVector();
163  G4Fragment* frag0 = new G4Fragment(theNucleus);
164  G4Fragment* frag1 = EmittedFragment(frag0);
165  if(frag1) { theResult->push_back(frag1); }
166  theResult->push_back(frag0);
167  return theResult;
168 }
169 
171  // Samples a isotropic random vectorwith a magnitud given by Magnitude.
172  // By default Magnitude = 1.0
173 {
174  G4double CosTheta = 1.0 - 2.0*G4UniformRand();
175  G4double SinTheta = std::sqrt(1.0 - CosTheta*CosTheta);
176  G4double Phi = twopi*G4UniformRand();
177  G4ThreeVector Vector(Magnitude*std::cos(Phi)*SinTheta,
178  Magnitude*std::sin(Phi)*SinTheta,
179  Magnitude*CosTheta);
180  return Vector;
181 }
static G4double GetNuclearMass(const G4double A, const G4double Z)
CLHEP::Hep3Vector G4ThreeVector
virtual G4Fragment * EmittedFragment(G4Fragment *theNucleus)
G4double SampleKineticEnergy(G4double minKineticEnergy, G4double maxKineticEnergy)
virtual G4double GetEmissionProbability(G4Fragment *fragment)
int G4int
Definition: G4Types.hh:78
G4VLevelDensityParameter * theLevelDensityPtr
#define G4UniformRand()
Definition: Randomize.hh:97
G4int GetA_asInt() const
Definition: G4Fragment.hh:251
G4PairingCorrection * pairingCorrection
const G4LorentzVector & GetMomentum() const
Definition: G4Fragment.hh:284
void SetMomentum(const G4LorentzVector &value)
Definition: G4Fragment.hh:289
static const double twopi
Definition: G4SIunits.hh:75
G4double GetPairingCorrection(G4int A, G4int Z) const
std::vector< G4Fragment * > G4FragmentVector
Definition: G4Fragment.hh:63
G4double GetGroundStateMass() const
Definition: G4Fragment.hh:273
G4VCoulombBarrier * theCoulombBarrier
static G4PairingCorrection * GetInstance()
G4EvaporationChannel(G4int theA, G4int theZ, const G4String &aName, G4EvaporationProbability *aEmissionStrategy, G4VCoulombBarrier *aCoulombBarrier)
G4EvaporationProbability * theProbability
T max(const T t1, const T t2)
brief Return the largest of the two arguments
void SetZandA_asInt(G4int Znew, G4int Anew)
Definition: G4Fragment.hh:261
virtual G4FragmentVector * BreakUp(const G4Fragment &theNucleus)
G4int GetZ_asInt() const
Definition: G4Fragment.hh:256
virtual G4double GetCoulombBarrier(G4int ARes, G4int ZRes, G4double U) const =0
G4ThreeVector IsotropicVector(G4double Magnitude=1.0)
double G4double
Definition: G4Types.hh:76
G4double GetExcitationEnergy() const
Definition: G4Fragment.hh:268
CLHEP::HepLorentzVector G4LorentzVector