Convert all photon physics except bremsstrahlung (not done yet)

include/openmc/endf.h

@@ -78,6 +78,10 @@ public:
   //! \param[in] x independent variable
   //! \return Function evaluated at x
   double operator()(double x) const;
+
+  // Accessors
+  const std::vector<double>& x() const { return x_; }
+  const std::vector<double>& y() const { return y_; }
 private:
   std::size_t n_regions_ {0}; //!< number of interpolation regions
   std::vector<int> nbt_; //!< values separating interpolation regions

include/openmc/math_functions.h

@@ -129,7 +129,7 @@ extern "C" void calc_zn_rad(int n, double rho, double zn_rad[]);
 //!   is passed
 //==============================================================================
 
-extern "C" void rotate_angle_c(double uvw[3], double mu, double* phi);
+extern "C" void rotate_angle_c(double uvw[3], double mu, const double* phi);
 
 Direction rotate_angle(Direction u, double mu, double* phi);
 

include/openmc/photon.h

@@ -2,12 +2,14 @@
 #define OPENMC_PHOTON_H
 
 #include "openmc/endf.h"
+#include "openmc/particle.h"
 
 #include <hdf5.h>
 #include "xtensor/xtensor.hpp"
 
 #include <string>
 #include <unordered_map>
+#include <utility> // for pair
 #include <vector>
 
 namespace openmc {
@@ -39,6 +41,17 @@ public:
   // Constructors
   PhotonInteraction(hid_t group);
 
+  // Methods
+  void compton_scatter(double alpha, bool doppler, double* alpha_out,
+    double* mu, int* i_shell) const;
+
+  double rayleigh_scatter(double alpha) const;
+
+  void pair_production(double alpha, double* E_electron, double* E_positron,
+    double* mu_electron, double* mu_positron) const;
+
+  void atomic_relaxation(const ElectronSubshell& shell, Particle& p) const;
+
   // Data members
   std::string name_; //! Name of element, e.g. "Zr"
   int Z_; //! Atomic number
@@ -76,6 +89,9 @@ public:
 
   // Bremsstrahlung scaled DCS
   xt::xtensor<double, 2> dcs_;
+
+private:
+  void compton_doppler(double alpha, double mu, double* E_out, int* i_shell) const;
 };
 
 //==============================================================================
@@ -94,6 +110,14 @@ struct ElementMicroXS {
   double pair_production; //!< microscopic pair production xs
 };
 
+//==============================================================================
+// Non-member functions
+//==============================================================================
+
+std::pair<double, double> klein_nishina(double alpha);
+
+void thick_target_bremsstrahlung(Particle& p, double* E_lost);
+
 //==============================================================================
 // Global variables
 //==============================================================================

include/openmc/physics.h

@@ -22,7 +22,7 @@ void sample_neutron_reaction(Particle* p);
 //! Samples an element based on the macroscopic cross sections for each nuclide
 //! within a material and then samples a reaction for that element and calls the
 //! appropriate routine to process the physics.
-extern "C" void sample_photon_reaction(Particle* p);
+void sample_photon_reaction(Particle* p);
 
 //! Terminates the particle and either deposits all energy locally
 //! (electron_treatment = ELECTRON_LED) or creates secondary bremsstrahlung
@@ -44,7 +44,7 @@ void sample_nuclide(const Particle* p, int mt, int* i_nuclide, int* i_nuc_mat);
 void create_fission_sites(Particle* p, int i_nuclide, const Reaction* rx,
   Bank* bank_array, int64_t* bank_size, int64_t bank_capacity);
 
-// void sample_element(Particle* p);
+extern "C" int sample_element(Particle* p);
 
 Reaction* sample_fission(int i_nuclide, double E);