Geant4 9.6.0
Toolkit for the simulation of the passage of particles through matter
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Public Member Functions | List of all members
G4TripathiLightCrossSection Class Reference

#include <G4TripathiLightCrossSection.hh>

+ Inheritance diagram for G4TripathiLightCrossSection:

Public Member Functions

 G4TripathiLightCrossSection ()
 
 ~G4TripathiLightCrossSection ()
 
virtual G4bool IsElementApplicable (const G4DynamicParticle *theProjectile, G4int Z, const G4Material *)
 
virtual G4double GetElementCrossSection (const G4DynamicParticle *theProjectile, G4int Z, const G4Material *mat=0)
 
void SetLowEnergyCheck (G4bool)
 
- Public Member Functions inherited from G4VCrossSectionDataSet
 G4VCrossSectionDataSet (const G4String &nam="")
 
virtual ~G4VCrossSectionDataSet ()
 
virtual G4bool IsElementApplicable (const G4DynamicParticle *, G4int Z, const G4Material *mat=0)
 
virtual G4bool IsIsoApplicable (const G4DynamicParticle *, G4int Z, G4int A, const G4Element *elm=0, const G4Material *mat=0)
 
G4double GetCrossSection (const G4DynamicParticle *, const G4Element *, const G4Material *mat=0)
 
G4double ComputeCrossSection (const G4DynamicParticle *, const G4Element *, const G4Material *mat=0)
 
virtual G4double GetElementCrossSection (const G4DynamicParticle *, G4int Z, const G4Material *mat=0)
 
virtual G4double GetIsoCrossSection (const G4DynamicParticle *, G4int Z, G4int A, const G4Isotope *iso=0, const G4Element *elm=0, const G4Material *mat=0)
 
virtual G4Isotope * SelectIsotope (const G4Element *, G4double kinEnergy)
 
virtual void BuildPhysicsTable (const G4ParticleDefinition &)
 
virtual void DumpPhysicsTable (const G4ParticleDefinition &)
 
virtual void CrossSectionDescription (std::ostream &) const
 
void SetVerboseLevel (G4int value)
 
G4double GetMinKinEnergy () const
 
void SetMinKinEnergy (G4double value)
 
G4double GetMaxKinEnergy () const
 
void SetMaxKinEnergy (G4double value)
 
const G4String & GetName () const
 

Additional Inherited Members

- Protected Member Functions inherited from G4VCrossSectionDataSet
void SetName (const G4String &)
 
- Protected Attributes inherited from G4VCrossSectionDataSet
G4int verboseLevel
 

Detailed Description

Definition at line 83 of file G4TripathiLightCrossSection.hh.

Constructor & Destructor Documentation

◆ G4TripathiLightCrossSection()

G4TripathiLightCrossSection::G4TripathiLightCrossSection ( )

Definition at line 77 of file G4TripathiLightCrossSection.cc.

78 : G4VCrossSectionDataSet("TripathiLightIons")
79{
80 // Constructor only needs to instantiate the object which provides functions
81 // to calculate the nuclear radius, and some other constants used to
82 // calculate cross-sections.
83
84 theWilsonRadius = new G4WilsonRadius();
85 r_0 = 1.1 * fermi;
86
87 // The following variable is set to true if
88 // G4TripathiLightCrossSection::GetCrossSection is going to be called from
89 // within G4TripathiLightCrossSection::GetCrossSection to check whether the
90 // cross-section is behaviing anomalously in the low-energy region.
91
92 lowEnergyCheck = false;
93}

◆ ~G4TripathiLightCrossSection()

G4TripathiLightCrossSection::~G4TripathiLightCrossSection ( )

Definition at line 96 of file G4TripathiLightCrossSection.cc.

97{
98 //
99 // Destructor just needs to delete the pointer to the G4WilsonRadius object.
100 //
101 delete theWilsonRadius;
102}

Member Function Documentation

◆ GetElementCrossSection()

G4double G4TripathiLightCrossSection::GetElementCrossSection ( const G4DynamicParticle *  theProjectile,
G4int  Z,
const G4Material *  mat = 0 
)
virtual

Reimplemented from G4VCrossSectionDataSet.

Definition at line 125 of file G4TripathiLightCrossSection.cc.

127{
128 // Initialise the result.
129 G4double result = 0.0;
130
131 // Get details of the projectile and target (nucleon number, atomic number,
132 // kinetic enery and energy/nucleon.
133
134 G4double xAT= G4NistManager::Instance()->GetAtomicMassAmu(ZT);
135 G4int AT = G4lrint(xAT);
136 G4double EA = theProjectile->GetKineticEnergy()/MeV;
137 G4int AP = theProjectile->GetDefinition()->GetBaryonNumber();
138 G4double xAP= G4double(AP);
139 G4double ZP = G4lrint(theProjectile->GetDefinition()->GetPDGCharge()/eplus);
140 G4double E = EA / xAP;
141
142 G4Pow* g4pow = G4Pow::GetInstance();
143
144 G4double AT13 = g4pow->Z13(AT);
145 G4double AP13 = g4pow->Z13(AP);
146
147 // Determine target mass and energy within the centre-of-mass frame.
148
149 G4double mT = G4NucleiProperties::GetNuclearMass(AT, ZT);
150 G4LorentzVector pT(0.0, 0.0, 0.0, mT);
151 G4LorentzVector pP(theProjectile->Get4Momentum());
152 pT += pP;
153 G4double E_cm = (pT.mag()-mT-pP.m())/MeV;
154
155 //G4cout << G4endl;
156 //G4cout << "### EA= " << EA << " ZT= " << ZT << " AT= " << AT
157 // << " ZP= " << ZP << " AP= " << AP << " E_cm= " << E_cm
158 // << " Elim= " << (0.8 + 0.04*ZT)*xAP << G4endl;
159
160 if (E_cm <= 0.0) { return 0.; }
161 if (E_cm <= (0.8 + 0.04*ZT)*xAP && !lowEnergyCheck) { return 0.; }
162
163 G4double E_cm13 = g4pow->A13(E_cm);
164
165 // Determine nuclear radii. Note that the r_p and r_T are defined differently
166 // from Wilson et al.
167
168 G4double r_rms_p = theWilsonRadius->GetWilsonRMSRadius(xAP);
169 G4double r_rms_t = theWilsonRadius->GetWilsonRMSRadius(xAT);
170
171 G4double r_p = 1.29*r_rms_p;
172 G4double r_t = 1.29*r_rms_t;
173
174 G4double Radius = (r_p + r_t)/fermi + 1.2*(AT13 + AP13)/E_cm13;
175
176 G4double B = 1.44 * ZP * ZT / Radius;
177
178 // Now determine other parameters associated with the parametric
179 // formula, depending upon the projectile and target.
180
181 G4double T1 = 0.0;
182 G4double D = 0.0;
183 G4double G = 0.0;
184
185 if ((AT==1 && ZT==1) || (AP==1 && ZP==1)) {
186 T1 = 23.0;
187 D = 1.85 + 0.16/(1+std::exp((500.0-E)/200.0));
188
189 } else if ((AT==1 && ZT==0) || (AP==1 && ZP==0)) {
190 T1 = 18.0;
191 D = 1.85 + 0.16/(1+std::exp((500.0-E)/200.0));
192
193 } else if ((AT==2 && ZT==1) || (AP==2 && ZP==1)) {
194 T1 = 23.0;
195 D = 1.65 + 0.1/(1+std::exp((500.0-E)/200.0));
196
197 } else if ((AT==3 && ZT==2) || (AP==3 && ZP==2)) {
198 T1 = 40.0;
199 D = 1.55;
200
201 } else if (AP==4 && ZP==2) {
202 if (AT==4 && ZT==2) {T1 = 40.0; G = 300.0;}
203 else if (ZT==4) {T1 = 25.0; G = 300.0;}
204 else if (ZT==7) {T1 = 40.0; G = 500.0;}
205 else if (ZT==13) {T1 = 25.0; G = 300.0;}
206 else if (ZT==26) {T1 = 40.0; G = 300.0;}
207 else {T1 = 40.0; G = 75.0;}
208 D = 2.77 - 8.0E-3*AT + 1.8E-5*AT*AT-0.8/(1.0+std::exp((250.0-E)/G));
209 }
210 else if (AT==4 && ZT==2) {
211 if (AP==4 && ZP==2) {T1 = 40.0; G = 300.0;}
212 else if (ZP==4) {T1 = 25.0; G = 300.0;}
213 else if (ZP==7) {T1 = 40.0; G = 500.0;}
214 else if (ZP==13) {T1 = 25.0; G = 300.0;}
215 else if (ZP==26) {T1 = 40.0; G = 300.0;}
216 else {T1 = 40.0; G = 75.0;}
217 D = 2.77 - 8.0E-3*AP + 1.8E-5*AP*AP-0.8/(1.0+std::exp((250.0-E)/G));
218 }
219
220 // C_E, S, deltaE, X1, S_L and X_m correspond directly with the original
221 // formulae of Tripathi et al in his report.
222 //G4cout << "E= " << E << " T1= " << T1 << " AP= " << AP << " ZP= " << ZP
223 // << " AT= " << AT << " ZT= " << ZT << G4endl;
224 G4double C_E = D*(1.0-std::exp(-E/T1)) -
225 0.292*std::exp(-E/792.0)*std::cos(0.229*std::pow(E,0.453));
226
227 G4double S = AP13*AT13/(AP13 + AT13);
228
229 G4double deltaE = 0.0;
230 G4double X1 = 0.0;
231 if (AT >= AP)
232 {
233 deltaE = 1.85*S + 0.16*S/E_cm13 - C_E + 0.91*(AT-2*ZT)*ZP/(xAT*xAP);
234 X1 = 2.83 - 3.1E-2*AT + 1.7E-4*AT*AT;
235 }
236 else
237 {
238 deltaE = 1.85*S + 0.16*S/E_cm13 - C_E + 0.91*(AP-2*ZP)*ZT/(xAT*xAP);
239 X1 = 2.83 - 3.1E-2*AP + 1.7E-4*AP*AP;
240 }
241 G4double S_L = 1.2 + 1.6*(1.0-std::exp(-E/15.0));
242 //JMQ 241110 bug fixed
243 G4double X_m = 1.0 - X1*std::exp(-E/(X1*S_L));
244
245 //G4cout << "deltaE= " << deltaE << " X1= " << X1 << " S_L= " << S_L << " X_m= " << X_m << G4endl;
246
247 // R_c is also highly dependent upon the A and Z of the projectile and
248 // target.
249
250 G4double R_c = 1.0;
251 if (AP==1 && ZP==1)
252 {
253 if (AT==2 && ZT==1) R_c = 13.5;
254 else if (AT==3 && ZT==2) R_c = 21.0;
255 else if (AT==4 && ZT==2) R_c = 27.0;
256 else if (ZT==3) R_c = 2.2;
257 }
258 else if (AT==1 && ZT==1)
259 {
260 if (AP==2 && ZP==1) R_c = 13.5;
261 else if (AP==3 && ZP==2) R_c = 21.0;
262 else if (AP==4 && ZP==2) R_c = 27.0;
263 else if (ZP==3) R_c = 2.2;
264 }
265 else if (AP==2 && ZP==1)
266 {
267 if (AT==2 && ZT==1) R_c = 13.5;
268 else if (AT==4 && ZT==2) R_c = 13.5;
269 else if (AT==12 && ZT==6) R_c = 6.0;
270 }
271 else if (AT==2 && ZT==1)
272 {
273 if (AP==2 && ZP==1) R_c = 13.5;
274 else if (AP==4 && ZP==2) R_c = 13.5;
275 else if (AP==12 && ZP==6) R_c = 6.0;
276 }
277 else if ((AP==4 && ZP==2 && (ZT==73 || ZT==79)) ||
278 (AT==4 && ZT==2 && (ZP==73 || ZP==79))) R_c = 0.6;
279
280 // Find the total cross-section. Check that it's value is positive, and if
281 // the energy is less that 10 MeV/nuc, find out if the cross-section is
282 // increasing with decreasing energy. If so this is a sign that the function
283 // is behaving badly at low energies, and the cross-section should be
284 // set to zero.
285
286 G4double xr = r_0*(AT13 + AP13 + deltaE);
287 result = pi * xr * xr * (1.0 - R_c*B/E_cm) * X_m;
288 //G4cout << " result= " << result << " E= " << E << " check= "<< lowEnergyCheck << G4endl;
289 if (result < 0.0) {
290 result = 0.0;
291
292 } else if (!lowEnergyCheck && E < 6.0) {
293 G4double f = 0.95;
294 G4DynamicParticle slowerProjectile = *theProjectile;
295 slowerProjectile.SetKineticEnergy(f * EA * MeV);
296
297 G4bool savelowenergy = lowEnergyCheck;
298 SetLowEnergyCheck(true);
299 G4double resultp = GetElementCrossSection(&slowerProjectile, ZT);
300 SetLowEnergyCheck(savelowenergy);
301 //G4cout << " newres= " << resultp << " f*EA= " << f*EA << G4endl;
302 if (resultp > result) { result = 0.0; }
303 }
304
305 return result;
306}
G4double
double G4double
Definition: G4Types.hh:64
G4int
int G4int
Definition: G4Types.hh:66
G4bool
bool G4bool
Definition: G4Types.hh:67
G4DynamicParticle::GetDefinition
G4ParticleDefinition * GetDefinition() const
G4DynamicParticle::Get4Momentum
G4LorentzVector Get4Momentum() const
G4DynamicParticle::GetKineticEnergy
G4double GetKineticEnergy() const
G4DynamicParticle::SetKineticEnergy
void SetKineticEnergy(G4double aEnergy)
G4NistManager::Instance
static G4NistManager * Instance()
Definition: G4NistManager.cc:68
G4NistManager::GetAtomicMassAmu
G4double GetAtomicMassAmu(const G4String &symb) const
Definition: G4NistManager.hh:343
G4NucleiProperties::GetNuclearMass
static G4double GetNuclearMass(const G4double A, const G4double Z)
Definition: G4NucleiProperties.cc:53
G4ParticleDefinition::GetPDGCharge
G4double GetPDGCharge() const
Definition: G4ParticleDefinition.hh:119
G4Pow
Definition: G4Pow.hh:54
G4Pow::GetInstance
static G4Pow * GetInstance()
Definition: G4Pow.cc:50
G4Pow::A13
G4double A13(G4double A)
Definition: G4Pow.hh:115
G4Pow::Z13
G4double Z13(G4int Z)
Definition: G4Pow.hh:110
G4TripathiLightCrossSection::GetElementCrossSection
virtual G4double GetElementCrossSection(const G4DynamicParticle *theProjectile, G4int Z, const G4Material *mat=0)
Definition: G4TripathiLightCrossSection.cc:125
G4WilsonRadius::GetWilsonRMSRadius
G4double GetWilsonRMSRadius(G4double A)
Definition: G4WilsonRadius.cc:80
G4INCL::Math::pi
const G4double pi
Definition: G4INCLGlobals.hh:70
G4lrint
int G4lrint(double ad)
Definition: templates.hh:163

Referenced by GetElementCrossSection().

◆ IsElementApplicable()

G4bool G4TripathiLightCrossSection::IsElementApplicable ( const G4DynamicParticle *  theProjectile,
G4int  Z,
const G4Material *   
)
virtual

Reimplemented from G4VCrossSectionDataSet.

Definition at line 106 of file G4TripathiLightCrossSection.cc.

108{
109 G4bool result = false;
110 G4int AT = G4lrint(G4NistManager::Instance()->GetAtomicMassAmu(ZT));
111 G4int ZP = G4lrint(theProjectile->GetDefinition()->GetPDGCharge()/eplus);
112 G4int AP = theProjectile->GetDefinition()->GetBaryonNumber();
113 if (theProjectile->GetKineticEnergy()/AP < 10.0*GeV &&
114 ((AT==1 && ZT==1) || (AP==1 && ZP==1) ||
115 (AT==1 && ZT==0) || (AP==1 && ZP==0) ||
116 (AT==2 && ZT==1) || (AP==2 && ZP==1) ||
117 (AT==3 && ZT==2) || (AP==3 && ZP==2) ||
118 (AT==4 && ZT==2) || (AP==4 && ZP==2))) { result = true; }
119 return result;
120}

Referenced by G4GeneralSpaceNNCrossSection::GetElementCrossSection().

◆ SetLowEnergyCheck()

void G4TripathiLightCrossSection::SetLowEnergyCheck ( G4bool  aLowEnergyCheck)
inline

Definition at line 107 of file G4TripathiLightCrossSection.hh.

108{
109 lowEnergyCheck = aLowEnergyCheck;
110}

Referenced by GetElementCrossSection().

The documentation for this class was generated from the following files: