Geant4  10.01.p01
G4InuclParamAngDst.cc
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26 // $Id$
27 // Author: Michael Kelsey (SLAC)
28 // Date: 22 April 2013
29 //
30 // Description: intermediate base class for INUCL parametrizations of
31 // three-body angular distributions in Bertini-style cascade
32 //
33 // 20130308 M. Kelsey -- Move PQ,PR calculation to G4InuclSpecialFunctions.
34 
35 #include "G4InuclParamAngDst.hh"
37 #include "G4InuclParticleNames.hh"
38 using namespace G4InuclSpecialFunctions;
39 using namespace G4InuclParticleNames;
40 
41 
42 // Use coefficients in power expansion of random fraction
43 
45  if (verboseLevel>3) {
46  G4cout << theName << "::GetCosTheta: ptype " << ptype << " ekin " << ekin
47  << G4endl;
48  }
49 
50  G4int J = (ptype==pro || ptype==neu) ? 0 : 1; // nucleon vs. other
51  if (verboseLevel > 3) G4cout << " J " << J << G4endl;
52 
53  const G4int itry_max = 100; // Parametrizations aren't properly bounded
54 
55  G4double Spow = -999.;
56  G4int itry = 0;
57  while ((Spow < 0. || Spow > 1.) && itry < itry_max) {
58  itry++;
59  Spow = randomInuclPowers(ekin, coeffAB[J]);
60  }
61 
62  if (itry == itry_max) { // No success, just throw flat distribution
63  if (verboseLevel > 2) {
64  G4cout << theName << "::GetCosTheta -> itry = itry_max " << itry
65  << G4endl;
66  }
67 
68  Spow = inuclRndm();
69  }
70 
71  return 2.0*Spow - 1.0; // Convert generated [0..1] to [-1..1]
72 }
virtual G4double GetCosTheta(G4int ptype, G4double ekin) const
int G4int
Definition: G4Types.hh:78
G4GLOB_DLL std::ostream G4cout
G4double randomInuclPowers(G4double ekin, const G4double(&coeff)[4][4])
#define G4endl
Definition: G4ios.hh:61
double G4double
Definition: G4Types.hh:76