#ifndef CONSTANTS__AAHH_INCLUDED
#define CONSTANTS__AAHH_INCLUDED

#include <iostream>
#include <cmath>

namespace aa 
{
const double water_index           = 1.3499;
const double dndl                  = 0.0298;
const double c_light               = 299792458*1e-9;
const double v_light               = c_light/(water_index + dndl);
const double cos_cherenkov_angle   = 1.0 / water_index;
const double cherenkov_angle       = acos( cos_cherenkov_angle );
const double pi                    = acos(-1);
const double deg                   = 180/pi;
const double aaver                 = 2.0;

inline void print_constants()
{
  std::cout << " water_index          " <<  water_index          << std::endl;
  std::cout << " dndl                 " <<  dndl                 << std::endl;
  std::cout << " c_light              " <<  c_light              << std::endl;
  std::cout << " v_light              " <<  v_light              << std::endl;
  std::cout << " cos_cherenkov_angle  " <<  cos_cherenkov_angle  << std::endl;
  std::cout << " cherenkov_angle      " <<  cherenkov_angle      << std::endl;
  std::cout << " pi                   " <<  pi                   << std::endl;
  std::cout << " deg                  " <<  deg                  << std::endl;
  std::cout << " aaver                " <<  aaver                << std::endl;
}
}

#ifndef HEP_PHYSICAL_CONSTANTS_H // this is all horrible
using namespace aa;              // if we don't have CLHEP, we use aa by default
#endif

#endif