Added menate_R source files and updates CMakeLists.txt file to compile and install them.

menate_R is a special neutron interaction library that uses correct carbon inelastic cross
sections (important for simulating organic scintillator neutron detectors)

NPSimulation/Process/CMakeLists.txt

-add_library(NPSProcess SHARED Decay.cc BeamReaction.cc FastDriftElectron.cc NPIonIonInelasticPhysic.cc PhysicsList.cc G4DriftElectron.cc G4IonizationWithDE.cc G4DriftElectronPhysics.cc G4DEAbsorption.cc G4DEAmplification.cc G4DETransport.cc )
+add_library(NPSProcess SHARED Decay.cc BeamReaction.cc FastDriftElectron.cc NPIonIonInelasticPhysic.cc PhysicsList.cc G4DriftElectron.cc G4IonizationWithDE.cc G4DriftElectronPhysics.cc G4DEAbsorption.cc G4DEAmplification.cc G4DETransport.cc menate_R.cc)
 target_link_libraries(NPSProcess ${ROOT_LIBRARIES} ${Geant4_LIBRARIES} ${NPLib_LIBRARIES} -lNPInitialConditions -lNPInteractionCoordinates -lNPReactionConditions)

NPSimulation/Process/menate_R.hh

+//----------------------------------------------------------------------
+//----------------------------------------------------------------------
+//
+// menate_R.hh 
+//
+// Description - a GEANT4 discrete process that models neutron
+// elastic scattering with non-relativistic kinematics.
+//
+// started on 6 May 2008
+//
+// a class derived from G4VDiscreteProcess
+// - Includes all processes (elastic and inelastic) from original
+// menate program, including kinematics
+//
+// Written by: Brian Roeder, Postdoc - LPC Caen, Texas A&M Univ. 
+// email - broeder@comp.tamu.edu
+//
+// Translated from Fortran program menates.for by P. Desesquelles et al.
+// Nucl. Instr. and Meths. A 307 Pg. 366 (1991)
+// Uses cross sections from A. Del Geuerra et al., NIM 135 Pg. 337 (1976).
+// except for n-p and n-12C elastic scattering total cross sections 
+// that come from MCNPx.
+//-----------------------------------------------------------------------
+//-----------------------------------------------------------------------
+// To include in physics list :
+//  #include "menate_R.hh"
+//  pManager = G4Neutron::Neutron()->GetProcessManager();
+// 	
+//    G4String NeutronProcessName = "menateR_neutron";
+//    menate_R* theMenate = new menate_R(NeutronProcessName);
+//    theMenate->SetMeanFreePathCalcMethod("ORIGINAL");
+//
+//  pManager->AddDiscreteProcess(theMenate);
+// 
+// -> Need also to set an environment variable called: MENATEG4XS
+//    to point towards the total cross section data file directory.
+//-----------------------------------------------------------------------
+//-----------------------------------------------------------------------
+// version comments
+//----------------------------------------------------------------------
+// version 0.1 - 18 Apr. 2008
+// added elastic scattering and kinetmatics from :
+// n+H1 -> n + p out (elastic)
+// n+12C -> n + 12C (elastic)
+//------------------------------------------------------------
+// version 1.0 - 23 Apr 2008 -> working version
+// modified functions and cross section read-in functions
+// added all reactions considered in original MENATE including:
+// n+H -> n+p elastic
+// n+12C -> n+12C elastic
+// n+12C -> n'+12C+gamma(4.4MeV)
+// n+12C -> a+9Be
+// n+12C -> n'+ 3a
+// n+12C -> p + 12B
+// n+12C -> n' + p + 11B (breakup)
+// n+12C -> n' + n + 11C (breakup)
+// All reactions considered together for MeanFreePath and
+// reaction probability consideration
+// MeanFreePath considers only total reaction probability
+// PostStepDoIt chooses reaction
+// **** This version includes fix in "Available_Eng" for
+// Alpha2 in process 12C(n,n')3a (bug in FORTRAN version of MENATE)
+//-------------------------------------------------------------------------
+//-------------------------------------------------------------------------
+// version 1.1 - 24 Apr 2008 -> working version
+// added function "ShareGammaEngC12()" to kinematics for 12C(n,n'g)12C*
+// process as in original MENATE FORTRAN code. This change effects NE213
+// efficiency in DEMON module between about 5-11 MeV, making the result
+// of the GEANT+MENATE efficiency calc. closer to that obtained by original
+// MENATE code. Efficiency below 5 MeV in GEANT code not changed.
+//-------------------------------------------------------------------------
+//-------------------------------------------------------------------------
+// 25 April 2008 - version 1.2 BTR
+// ---- Add Normalization of Momentum ThreeVector in GenMomDir to avoid
+// G4 Error Message. Noted that Norm diff from 1 is always less then 1e-7, so 
+// error is probably due to slight rounding error.
+//-------------------------------------------------------------------------
+// 28 April 2008 - version 1.2b BTR
+// ---- Added getenv command to ReadCrossSectionFile() Function
+// Program looks for environment variable MENATEG4XS to find cross sections
+// for use with menate.cc, otherwise throws exception.
+//-------------------------------------------------------------------------
+// 29 April 2008 - version 1.3 BTR
+// --- Noted that MeanFreePath and reaction selection calculations are 
+// different from method used in previous version. Added function
+// SetMeanFreePathCalcMethod() to switch between calc in previous
+// version and that method used specifically by MENATE
+// Modified GetMeanFreePath() and ChooseReaction() part of PostStepDoIt to add
+// MENATE original method.
+//---------------------------------------------------------------------------
+// 6 May 2008 - version 1.4 BTR
+// --- Begin modification to original MENATE code. Remove parts with no sense
+// (such as 400 keV gammas from 12C). Include angular distributions.
+//
+// 19 May 2008 - Finished revisions to version 1.4 BTR
+// --- Added parameterizations of angular distributions for n+p elastic
+// and n+12C elastic. (n+p, DEMONS), (n+12C, modified DEMONS). 
+// Now using ENDF cross sections for n+p and n+12C elastic
+// scattering. Extended total cross sections out to 999 MeV using total cross
+// sections from DEMONS (Los Alamos) program. 
+// Note : This version leaves the inelastic 12C(n,n') processes as isotropic.
+// in the center of mass cross section.
+// -------------------------------------------------------------------------- 
+// 2011-2012 Zach Kohley, see .hh file for detials of modification and addition
+// of Al and Fe material
+//--------------------------------------------------------------------------
+//
+// 6 Sept 2018
+// Added to NPTool package by Greg Christian (TAMU), gchristian@tamu.edu
+// Code inherited from MoNA-simulation package,
+// https://github.com/baumann3141/MoNA-simulation
+//
+// See menate_R.cc for list of changes made w.r.t. the
+// MoNA-simulation version
+
+#ifndef menate_R_hh 
+#define menate_R_hh
+
+#include "globals.hh"
+#include "G4VDiscreteProcess.hh"
+#include "G4ios.hh"
+#include "Randomize.hh" 
+#include "G4Track.hh"
+#include "G4Step.hh"
+#include "G4ParticleTypes.hh"
+#include "G4ParticleTable.hh"
+#include "G4IonTable.hh"
+#include "G4ParticleDefinition.hh"
+#include "G4DynamicParticle.hh"
+#include "G4ThreeVector.hh"
+#include "G4LorentzVector.hh"
+#include "G4VParticleChange.hh"
+
+#include "G4Material.hh"
+#include "G4UnitsTable.hh"
+
+#include "TH1F.h"
+
+#ifndef CS_Class
+#define CS_Class
+
+class CrossSectionClass
+{
+private:
+  // Data Members - each data member has one part of datafile!
+ 
+  G4String ElementName;
+
+  G4int NumberOfLines;
+  G4double KinEng;
+  G4double TotalCrossSection;
+
+public:
+
+  // constructor
+  CrossSectionClass()
+  {
+   NumberOfLines = 0;
+   ElementName = "Nothing";
+   KinEng = 0;
+   TotalCrossSection = 0;
+  }
+
+  // destructor
+  ~CrossSectionClass() 
+  {;}
+
+public:
+  // Setting and Access Functions
+
+  void SetNumberOfLines(G4int Lines)
+  { NumberOfLines = Lines; }
+
+  void SetElementName(G4String ElName)
+  { ElementName = ElName; }
+
+  void SetKinEng(G4double Energy)
+  { KinEng = Energy; }
+
+  void SetTotalCrossSection(G4double CrossSection)
+  { TotalCrossSection = CrossSection; }
+
+  G4int GetNumberOfLines()
+  { return NumberOfLines; }
+
+  G4String GetElementName()
+  { return ElementName; }
+
+  G4double GetKinEng()
+  { return KinEng; }
+
+  G4double GetTotalCrossSection()
+  { return TotalCrossSection; } 
+
+  void DumpData()
+  {
+    G4cout << "Number of Lines Total " << NumberOfLines
+           << ", Element Name = " << ElementName
+           << ", KinEng = " << KinEng
+           << " , CrossSection = " << TotalCrossSection << G4endl;
+  }
+
+}; 
+#endif 
+
+class menate_R : public G4VDiscreteProcess
+{
+public:
+
+  // constructor
+  menate_R(const G4String& processName="menate_R");
+
+  // destructor
+  ~menate_R();
+
+public:
+  // These are the functions in the Process: Derived from G4VDiscreteProcess.hh
+
+  G4bool IsApplicable(const G4ParticleDefinition& aParticle);
+  // Decides if process applicable or not. Only valid for Neutrons
+  // at some energy.
+
+  G4double GetMeanFreePath(const G4Track& aTrack, G4double previousStepSize,
+                           G4ForceCondition* condition); 
+  // Returns MeanFreePath for a particle in a given material in mm
+
+  G4VParticleChange* PostStepDoIt(const G4Track &aTrack, const G4Step &aStep);
+  // This is the important function where you define the process
+  // Returns steps, track and secondary particles
+
+  void SetMeanFreePathCalcMethod(G4String Method);
+
+private:
+
+ // Hide assignment operator as private 
+  menate_R& operator=(const menate_R &right);
+
+  // Copy constructor
+  menate_R(const menate_R&);
+
+  // Chooses Reaction in PostStepDoIt
+
+  G4String ChooseReaction();
+
+  // Other Pre-Defined Class Variables and Functions are below!
+
+  G4double Absolute(G4double Num);
+  G4double SIGN(G4double A1, G4double B2);
+ 
+  // Returns Cross Section for a given element, energy
+  G4double GetCrossSection(G4double KinEng, CrossSectionClass* theXS);
+
+  void ReadCrossSectionFile(G4String FileName, CrossSectionClass* theXS);
+
+  G4double GetXSInterpolation(G4double KinEng, G4double LEng, G4double HEng, 
+                               G4double LXS, G4double HXS);
+
+  // Functions translated from FORTRAN "MENATE" code 
+
+  G4ThreeVector GenMomDir(G4ThreeVector MomIn, G4double theta, G4double phi);
+
+  G4double ShareGammaEngC12(G4double A_Eng);
+
+  G4double Evaporate_Eng(G4double AMass, G4double Avail_Eng);
+
+  // Angular Distribution Generators
+
+  G4double NP_AngDist(G4double NEng);
+  G4double NC12_DIFF(G4double NEng);
+  void Setup_AlElastic_AngDist(); 
+  void Setup_FeElastic_AngDist(); 
+  G4double AlElastic_AngDist(G4double NEng); 
+  G4double FeElastic_AngDist(G4double NEng); 
+ 
+private:
+
+  // Class Variables
+
+  TH1F *hFe_AngDist_30MeV;
+  TH1F *hFe_AngDist_50MeV;
+  TH1F *hFe_AngDist_70MeV;
+  TH1F *hAl_AngDist_30MeV;
+  TH1F *hAl_AngDist_50MeV;
+  TH1F *hAl_AngDist_70MeV;
+
+
+
+  G4bool H_Switch;
+  G4bool C_Switch; 
+  G4bool Fe_Switch;
+  G4bool Al_Switch;
+
+  // Hold Number Density for H or C
+  G4double Num_H;  
+  G4double Num_C;
+  G4double Num_Fe;
+  G4double Num_Al;
+
+  // Variables used in MENATE functions above
+
+  G4double AMass_Material;  // Atomic Mass NE213 (according to MENATE)
+  G4String CalcMeth;
+
+  // integers for ShareGammaEngC12 Function
+  G4int Num_gamma_4439k;  // Num of 4.4MeV gammas
+
+  G4double Sigma;
+  G4double ProbDistPerReaction[12];
+  G4double ProbTot;
+
+  CrossSectionClass theHydrogenXS[181];
+  CrossSectionClass theCarbonXS[852];
+
+  CrossSectionClass theC12NGammaXS[37];
+  CrossSectionClass theC12ABe9XS[32];
+  CrossSectionClass theC12NPB12XS[15];
+
+  CrossSectionClass theC12NNPB11XS[10];
+  CrossSectionClass theC12N2NC11XS[11];
+  CrossSectionClass theC12NN3AlphaXS[35];
+
+  CrossSectionClass theIronElasXS[1040];
+  CrossSectionClass theIronNonelasXS[278];
+
+  CrossSectionClass theAlElasXS[380];
+  CrossSectionClass theAlNonelasXS[325];
+
+
+  // for storing current scattering element
+
+  G4String ElementName;
+  G4int A;             // Integer Mass of Recoil (from GetN())
+  G4int Z;             // Integer Charge of Recoil (from GetZ())
+
+  G4double Pi;
+  G4double Two_Pi;
+
+};
+#endif