| Geant4 Cross Reference |
1 // 1 //
2 // ******************************************* << 2 // This is the standard right-hand side for equation of motion.
3 // * License and Disclaimer <<
4 // * <<
5 // * The Geant4 software is copyright of th <<
6 // * the Geant4 Collaboration. It is provided <<
7 // * conditions of the Geant4 Software License <<
8 // * LICENSE and available at http://cern.ch/ <<
9 // * include a list of copyright holders. <<
10 // * <<
11 // * Neither the authors of this software syst <<
12 // * institutes,nor the agencies providing fin <<
13 // * work make any representation or warran <<
14 // * regarding this software system or assum <<
15 // * use. Please see the license in the file <<
16 // * for the full disclaimer and the limitatio <<
17 // * <<
18 // * This code implementation is the result <<
19 // * technical work of the GEANT4 collaboratio <<
20 // * By using, copying, modifying or distri <<
21 // * any work based on the software) you ag <<
22 // * use in resulting scientific publicati <<
23 // * acceptance of all terms of the Geant4 Sof <<
24 // ******************************************* <<
25 // 3 //
26 // G4EqMagElectricField implementation << 4 // The only case another is required is when using a moving reference
>> 5 // frame ... or extending the class to include additional Forces,
>> 6 // eg an electric field
27 // 7 //
28 // This is the standard right-hand side for eq << 8 // 10.11.98 V.Grichine
29 // 9 //
30 // The only case another is required is when u <<
31 // frame ... or extending the class to include <<
32 // e.g., an electric field <<
33 // <<
34 // Created: V.Grichine, 10.11.1998 <<
35 // ------------------------------------------- <<
36 <<
37 #include "G4EqMagElectricField.hh" 10 #include "G4EqMagElectricField.hh"
38 #include "globals.hh" <<
39 #include "G4PhysicalConstants.hh" <<
40 #include "G4SystemOfUnits.hh" <<
41 11
42 G4EqMagElectricField::G4EqMagElectricField(G4E << 12 void
43 : G4EquationOfMotion( emField ) << 13 G4EqMagElectricField::
>> 14 SetChargeMomentumMass( const G4double particleCharge, // e+ units
>> 15 const G4double MomentumXc,
>> 16 const G4double particleMass)
44 { 17 {
>> 18 fElectroMagCof = eplus*c_squared ;
>> 19 fElectroMagCof *= particleCharge/particleMass;
>> 20
45 } 21 }
46 22
47 G4EqMagElectricField::~G4EqMagElectricField() <<
48 23
49 void <<
50 G4EqMagElectricField::SetChargeMomentumMass(G4 <<
51 G4 <<
52 G4 <<
53 { <<
54 G4double pcharge = particleCharge.GetCharge <<
55 fElectroMagCof = eplus*pcharge*c_light ; <<
56 fMassCof = particleMass*particleMass ; <<
57 } <<
58 24
59 void 25 void
60 G4EqMagElectricField::EvaluateRhsGivenB(const << 26 G4EqMagElectricField::EvaluateRhsGivenB( const G4double y[],
61 const << 27 const G4double Field[],
62 << 28 G4double dydx[] ) const
63 { 29 {
>> 30
64 // Components of y: 31 // Components of y:
65 // 0-2 dr/ds, 32 // 0-2 dr/ds,
66 // 3-5 dp/ds - momentum derivatives << 33 // 3-5 dv/ds
67 << 34 // FCof() = charge/mass
68 G4double pSquared = y[3]*y[3] + y[4]*y[4] + <<
69 35
70 G4double Energy = std::sqrt( pSquared + f << 36 G4double vSquared = y[3]*y[3] + y[4]*y[4] + y[5]*y[5] ;
71 G4double cof2 = Energy/c_light ; <<
72 37
73 G4double pModuleInverse = 1.0/std::sqrt(pS << 38 G4double vModule = sqrt(vSquared) ;
74 39
75 G4double inverse_velocity = Energy * pModul << 40 G4double vDotE = y[3]*Field[3] + y[4]*Field[4] + y[5]*Field[5] ;
76 41
77 G4double cof1 = fElectroMagCof*pModuleI << 42 G4double gammaReci = sqrt(1 - vSquared/c_squared) ;
78 43
79 dydx[0] = y[3]*pModuleInverse ; << 44 dydx[0] = y[3]/vModule ;
80 dydx[1] = y[4]*pModuleInverse ; << 45 dydx[1] = y[4]/vModule ;
81 dydx[2] = y[5]*pModuleInverse ; << 46 dydx[2] = y[5]/vModule ;
82 47
83 dydx[3] = cof1*(cof2*Field[3] + (y[4]*Field << 48 dydx[3] = fElectroMagCof*(Field[3] + (y[4]*Field[2] - y[5]*Field[1])/c_light -
>> 49 y[3]*vDotE/c_light/c_light )*gammaReci/vModule ;
84 50
85 dydx[4] = cof1*(cof2*Field[4] + (y[5]*Field << 51 dydx[4] = fElectroMagCof*(Field[4] + (y[5]*Field[0] - y[3]*Field[2])/c_light -
>> 52 y[4]*vDotE/c_light/c_light )*gammaReci/vModule ;
86 53
87 dydx[5] = cof1*(cof2*Field[5] + (y[3]*Field << 54 dydx[5] = fElectroMagCof*(Field[5] + (y[3]*Field[1] - y[4]*Field[0])/c_light -
88 << 55 y[5]*vDotE/c_light/c_light)*gammaReci/vModule ;
89 dydx[6] = 0.;//not used << 56 return ;
90 <<
91 // Lab Time of flight <<
92 // <<
93 dydx[7] = inverse_velocity; <<
94 <<
95 return; <<
96 } 57 }
97 58