#ifndef ROOT_TCrossSection
#define ROOT_TCrossSection

#ifndef ROOT_TBuffer
#include "TBuffer.h"
#endif

class TPhoton;
class TLepton;
class TThreeVectorReal;

class TCrossSection {

public:
   virtual ~TCrossSection() { }

   static Double_t Compton(const TPhoton &gIn, const TLepton &eIn,
                           const TPhoton &gOut, const TLepton &eOut);
   static Double_t Bremsstrahlung(const TLepton &eIn, const TLepton &eOut,
                                  const TPhoton &gOut);
   static Double_t PairProduction(const TPhoton &gIn,
                                  const TLepton &eOut, const TLepton &pOut);

   void Print(Option_t *option="");

   ClassDef(TCrossSection,1)  // Several useful QED cross sections
};

#endif