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G4MonopoleEq.cc
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25 //
26 // G4MonopoleEq implementation
27 //
28 // Created: V.Grichine, 17.11.2009
29 // -------------------------------------------------------------------
30 
31 #include "G4MonopoleEq.hh"
32 #include "globals.hh"
33 #include "G4PhysicalConstants.hh"
34 #include "G4SystemOfUnits.hh"
35 
37  : G4EquationOfMotion( emField )
38 {
39 }
40 
42 {
43 }
44 
45 void
47  G4double,
48  G4double particleMass)
49 {
50  G4double pcharge = particleCharge.GetCharge();
51  fElectroMagCof = eplus*pcharge; // no *c_light as for ususal q
53 
54  fMassCof = particleMass*particleMass ;
55 }
56 
57 void
59  const G4double Field[],
60  G4double dydx[] ) const
61 {
62 
63  // Components of y:
64  // 0-2 dr/ds,
65  // 3-5 d(pc)/ds - momentum derivatives
66 
67  G4double pSquared = y[3]*y[3] + y[4]*y[4] + y[5]*y[5] ;
68 
69  G4double Energy = std::sqrt( pSquared + fMassCof );
70  G4double cof2 = Energy*c_light ;
71 
72  G4double pModuleInverse = 1.0/std::sqrt(pSquared) ;
73 
74  G4double inverse_velocity = Energy * pModuleInverse / c_light;
75 
76  G4double cof1 = fElectroMagCof*pModuleInverse ;
77 
78  dydx[0] = y[3]*pModuleInverse ;
79  dydx[1] = y[4]*pModuleInverse ;
80  dydx[2] = y[5]*pModuleInverse ;
81 
82  dydx[3] = cof1*(cof2*Field[0] - (y[4]*Field[5] - y[5]*Field[4])) ;
83 
84  dydx[4] = cof1*(cof2*Field[1] - (y[5]*Field[3] - y[3]*Field[5])) ;
85 
86  dydx[5] = cof1*(cof2*Field[2] - (y[3]*Field[4] - y[4]*Field[3])) ;
87 
88  dydx[6] = 0.; //not used
89 
90  // Lab Time of flight
91  //
92  dydx[7] = inverse_velocity;
93 
94  return;
95 }