constants.h

Go to the documentation of this file.

/*
 *    Copyright (c) 2013-2021,2023,2025
 *      SMASH Team
 *
 *    GNU General Public License (GPLv3 or later)
 */
#ifndef SRC_INCLUDE_SMASH_CONSTANTS_H_
#define SRC_INCLUDE_SMASH_CONSTANTS_H_
 
#include <cmath>
#include <cstdint>
#include <limits>
 
namespace smash {
 
template <typename T>
constexpr T smash_NaN = std::numeric_limits<T>::quiet_NaN();
 
constexpr double hbarc = 0.197327053;
 
constexpr double fm2_mb = 0.1;
 
constexpr double gev2_mb = hbarc * hbarc / fm2_mb;
 
constexpr double mev_to_gev = 1.e-3;
 
constexpr double really_small = 1.0e-6;
 
constexpr double very_small_double = 1.0e-15;
 
constexpr double twopi = 2. * M_PI;
 
constexpr double nuclear_density = 0.168;
 
constexpr double small_number = 1.0e-4;
 
constexpr double nucleon_mass = 0.938;
 
constexpr double pion_mass = 0.138;
 
constexpr double kaon_mass = 0.494;
 
constexpr double omega_mass = 0.783;
 
constexpr double delta_mass = 1.232;
constexpr double deuteron_mass = 1.8756;
 
constexpr double fine_structure = 7.2973525698e-3;
 
const double elementary_charge = std::sqrt(fine_structure * 4 * M_PI);
 
constexpr int maximum_rndm_seed_in_pythia = 900000000;
 
constexpr double minimum_sqrts_pythia_can_handle = 10.0;  // GeV
 
constexpr std::uint32_t ID_PROCESS_PHOTON =
    std::numeric_limits<std::uint32_t>::max();
 
}  // namespace smash
 
#endif  // SRC_INCLUDE_SMASH_CONSTANTS_H_