constants.h

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/*
 *  constants.h: header file for constants.
 *           
 *.............................................................................
 *    version 1:  May 1993   Simon F. Portegies Zwart
 *    version 2:
 *.............................................................................
 *     This file includes:
 *  1) definition of physical constants, assumed numbers and pre set
 *     numbers.
 *
 *.............................................................................
 */
#ifndef     _CONSTANTS
#   define  _CONSTANTS

#include "stdinc.h"       

#define static_cast(type, expr)         (type)(expr)
#define const_cast(type, expr)          (type)(expr)
#define reintepret_cast(type, expr)     (type)(expr)
#define dynamic_cast(type, expr)        (type)(expr)

#define SEBA_VERSION 2.0

#define TRUE 1
#define FALSE 0

// Stellar remnant constants.
// Remnant lifetimes.
//#define  SPI_TIME     0.0005               // Spiral in duration time.
#define  POST_AGB_TIME  0.005                // time to lose giant envelope.

//Assymetric supernovae kicks
#define MEAN_KICK 450.0                 // km/s
#define VAR_KICK  90.0                  // km/s

//#define BINARY_UPDATE_TIMESTEP 0.9      // Timestep increase for binary   
#define BINARY_UPDATE_TIMESTEP 0.1      // Timestep increase for binary   
#define TEN_PERCENT 0.1
//#define STABLE_ZETA 15
//#define J_SPI_FR 0.5                  //Pols 93 advises 1/3

// Model choices.
//#define exp_HE_lifetime FALSE         // exponential he star lifetime fits.

enum binary_history  {ms_ms = 0, bs_ms, bs_bs, he_ms, heN_ms, 
                      wr_ms, he_he, rscvn, 
                      wuma, wdxb, 
                      lmxb, mmxb, hmxb, spi, spi_2, 
                      wd_ms, wd_he, wd_wd, wd_ns, wdXns, 
                      pr_ms, pr_he, pr_st, prXst, pr_pr, prXpr,
                      ns_ms, ns_he, ns_st, nsXst, ns_ns, nsXns, st_st, 
                      no_of_type};

enum Be_binaries    {be_ms=0, be_he, be_wd, be_ns, no_of_be_binary};

enum mathematical_constant {one_third,
                            two_third,
                            pi,
                            two_pi
                        };
enum physics_constants{G, gravitational_constant,
                       C, speed_of_light,
                       Myear, million_years,
                       days, seconds_per_day,
                       km_per_s, kilometer_per_second,
                       kilometer, kilometer_in_centimeters,
                       nucleair_efficiency
                   };

enum astronomical_scale_parameter {PC, parsec,
                                   AU, astronomical_unit
                                };

enum solar_parameter {Msun, solar_mass,
                      Rsun, solar_radius,
                      Lsun, solar_luminosity,
                      Tsun, solar_temperature,
                      energy_to_mass_in_internal_units
};

enum pulsar_initial_conditions {pulsar_magnetic_field,
                                pulsar_pulse_period,
                                kanonical_neutron_star_radius,
                                kanonical_neutron_star_mass,
                                maximum_neutron_star_mass,
                                minimum_neutron_star_mass
                            };
    
enum stellar_mass_limits {low_mass_star_mass_limit,
                          medium_mass_star_mass_limit,
                          massive_star_mass_limit,
                          upper_ZAMS_mass_for_degenerate_core,
                          minimum_main_sequence,
                          maximum_planet_mass,
                          helium_dwarf_mass_limit,
                          carbon_dwarf_mass_limit,
                          Chandrasekar_mass,
//                        neutron_star,
//                        minimum_neutron_star,
//                        maximum_neutron_star,
                          helium2neutron_star,
                          COcore2black_hole,
                          core2blackhole_mass_fraction,
                          super_giant2neutron_star,
                          super_giant2black_hole,
                          maximum_main_sequence,
                          minimum_helium_star,
                          helium_star_lifetime_fraction,
                          helium_star_final_core_fraction
                      };

enum boolean_parameter {hyper_critical,
                        super_giant_disintegration,
                        proto_star_to_binary,
                        impulse_kick_for_black_holes,
                        use_angular_momentum_gamma
                     };

enum super_nova_kick_distribution {internally_decided_velocity_kick,
                                   no_velocity_kick,
                                   Maxwellian_velocity_kick,
                                   Paczynski_velocity_kick,
                                   delta_function_velocity_kick
                                  };

enum accretion_parameter {black_hole_accretion_limit,
                          neutron_star_accretion_limit,
                          white_dwarf_accretion_limit,
                          thermo_nuclear_flash
                      };

enum model_parameter {star_formation_efficiency,
                      star_formation_timescale,
                      magnetic_mass_limit,
                      magnetic_braking_exponent,
                      corotation_eccentricity,
                      tidal_circularization_radius,
                      core_overshoot,
                      hydrogen_fraction,
                      common_envelope_efficiency,
                      envelope_binding_energy,
                      specific_angular_momentum_loss,
                      dynamic_mass_transfer_gamma,
                      non_massive_star_envelope_fraction_lost,
                      massive_star_envelope_fraction_lost,
                      relaxation_driven_mass_loss_constant,
                      time_independent_mass_loss_law,
                      massive_star_mass_loss_law,
                      Darwin_Riemann_instability_factor,
                      homogeneous_sphere_gyration_radius_sq,
                      radiative_star_gyration_radius_sq,
                      convective_star_gyration_radius_sq,
                      rejuvenation_exponent,
                      spiral_in_time,
                      scale_kick_to_escape_velocity
};

enum observational_parameter {B_emission_star_mass_limit,
                              Barium_star_mass_limit,
                              Blue_straggler_mass_limit
                     };


enum safety_parameter {timestep_factor,
                       maximum_binary_update_time_fraction,
                       minimum_timestep,
                       minimum_mass_step,
                       maximum_timestep,
                       maximum_recursive_calls
                      };

enum dynamics_update_parameter {stellar_mass_update_limit,
                                semi_major_axis_update_limit,
                                binary_update_time_fraction
                                };

static
class stellar_evolution_constants {  // Easy to have a name for compiling.
  public:

  real mathematics(mathematical_constant);
  real physics(physics_constants);

  real super_nova_kick(super_nova_kick_distribution pk =
                       internally_decided_velocity_kick,
                       const real v_disp = 600);
  
  real parameters(solar_parameter);
  real parameters(astronomical_scale_parameter);
  real parameters(pulsar_initial_conditions);
  real parameters(stellar_mass_limits);
  
  bool parameters(boolean_parameter);
  real parameters(accretion_parameter);
  real parameters(model_parameter);

  real parameters(observational_parameter);

  real safety(safety_parameter);

  real star_to_dyn(dynamics_update_parameter);

} cnsts;

#endif          // _CONSTANTS

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