Geant4  10.01.p03
G4InuclParamMomDst.cc
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26 // $Id: G4InuclParamMomDst.cc 67863 2013-03-11 19:00:21Z mkelsey $
27 // Author: Michael Kelsey (SLAC)
28 // Date: 7 March 2013
29 //
30 // Description: intermediate base class for INUCL parametrizations of
31 // final-state momentum distributions in Bertini-style cascade
32 //
33 // 20130308 M. Kelsey -- Move PQ,PR calculation to G4InuclSpecialFunctions.
34 // 20130924 M. Kelsey -- Replace std::pow with G4Pow::powN() for CPU speed
35 
36 #include "G4InuclParamMomDst.hh"
38 #include "G4InuclParticleNames.hh"
39 #include "G4Pow.hh"
40 #include "Randomize.hh"
41 
42 using namespace G4InuclSpecialFunctions;
43 using namespace G4InuclParticleNames;
44 
45 
46 // Use coefficients in power expansion of random fraction
47 
48 G4double
49 G4InuclParamMomDst::GetMomentum(G4int ptype, const G4double& ekin) const {
50  if (verboseLevel>3) {
51  G4cout << theName << "::GetMomentum: ptype " << ptype << " ekin " << ekin
52  << G4endl;
53  }
54 
55  G4int JK = (ptype==pro || ptype==neu) ? 0 : 1; // nucleon vs. other
56 
57  if (verboseLevel > 3) G4cout << " JK " << JK << G4endl;
58 
59  G4Pow* theG4Pow = G4Pow::GetInstance(); // For convenience
60 
61  G4double Spow = randomInuclPowers(ekin, coeffPR[JK]);
62 
63  G4double C=0., PS=0.;
64  for(G4int im = 0; im < 3; im++) {
65  C = coeffPS[JK][im];
66  PS += C * theG4Pow->powN(ekin, im);
67 
68  if (verboseLevel >3) {
69  G4cout << " im " << im << " : coeffPS[JK][im] " << C
70  << " ekin^im " << theG4Pow->powN(ekin, im) << G4endl;
71  }
72  }
73 
74  G4double PRA = PS * Spow;
75 
76  if (verboseLevel > 3)
77  G4cout << " PS " << PS << " Spow = sqrt(S)*(PR+(1-PQ)*S^4) " << Spow
78  << " PRA = PS*Spow " << PRA << G4endl;
79 
80  return std::fabs(PRA);
81 }
static G4Pow * GetInstance()
Definition: G4Pow.cc:55
G4double powN(G4double x, G4int n) const
Definition: G4Pow.cc:128
Definition: G4Pow.hh:56
int G4int
Definition: G4Types.hh:78
G4GLOB_DLL std::ostream G4cout
G4double randomInuclPowers(G4double ekin, const G4double(&coeff)[4][4])
virtual G4double GetMomentum(G4int ptype, const G4double &ekin) const
#define G4endl
Definition: G4ios.hh:61
double G4double
Definition: G4Types.hh:76